After arriving back at court in King’s Landing, Cersei is checking Prince Joffrey’s wounds. She tells him they can say what they like about the incident, that Joffrey fought off a direwolf  bravely. Cersei even suggests spreading the story that he killed the beast and only spared Arya  Stark because of the love his father bore for hers. Cersei says that the truth is malleable for a king, that once Aerys Targaryen sat on the Iron Throne and Robert was a rebel and traitor. When Joffrey sits on the Throne, the truth will be what he makes it. Joffrey asks if he has to marry Sansa and Cersei confirms this is so, but that he only has to sleep with her when he wants. She suggests doing something nice for Sansa Stark to try to repair their rift, but Joffrey is reluctant. Instead, he argues that they are allowing the Northerners too much power and they consider themselves the equals of the Lannisters and Baratheons. Cersei asks him how he would handle them and he suggests doubling their taxes and contributing ten-thousand men to a standing Royal Army. Joffrey thinks that each lord controlling his own force is primitive. If the Northerners were to rebel over this matter, Joffrey would seize Winterfell and install someone loyal – perhaps Cersei’s uncle Kevan Lannister – as Warden of the North. Cersei tells her son his plan is foolish: the North is too big and too wild to be invaded and occupied. Any occupying army would be annihilated when winter comes. A good king knows when to save his strength and destroy his enemies. Joffrey notes this and asks his mother if the Starks are their enemies. Cersei replies that, "Anyone who isn't us is an enemy."

That evening, Cersei meets with Jaime in her chambers for the first time since returning to the capital. The Queen berates him for pushing Bran Stark from the window. She insists that they could have intimidated Bran into silence. Jaime, however, tells her to calm down, stating that even if the boy reports anything they can claim he was “lying or dreaming.” Jaime assures that they can “outfox a ten-year-old.” Cersei then reports that Bran has no memory of what happened, which satisfies her brother. If somehow Bran eventually remembers and King Robert goes to war with him, Jaime will gladly fight. He jests that it can inspire a ballad written about them: “the War for Cersei’s Cunt.” Cersei angrily slaps him, as Jaime then pulls her into a hold, telling her he will kill everyone until the two of them are the only people left in the world if necessary.

Some days later, Queen Cersei and King Robert attend the first day of the tournament. A drunken Robert annoys Cersei to the point of her exiting the tourney before it’s even began. Sitting in the stands, Sansa Stark tries to catch Prince Joffrey's eye, but he avoids looking at her. Noting the exchange, Petyr 'Littlefinger' Baelish, a member of King Robert’s small council, asks if they are having a lover’s quarrel. He introduces himself as a friend of Sansa and Arya's mother Catelyn. Arya then asks why is he called Littlefinger. Septa Mordane admonishes her for rudeness, but Littlefinger says it is all right. He was born on the smallest of the Fingers, the peninsulas that extend into the Narrow Sea on the east coast of the Vale of Arryn, and was very small as a boy, so it was a clever joke. The first tilt is then held and the first of the combatants is Ser Gregor Clegane, a gigantic man over seven feet in height. He is called "the Mountain". He is the elder brother of Sandor Clegane, Prince Joffrey's bodyguard. His opponent is Ser Hugh of the Vale. On their second pass, Gregor's lance takes Ser Hugh in the throat, killing him. Baelish notes this was an unfortunate accident and then asks Sansa if she has ever heard the tale of the Mountain and the Hound. When they were children, Gregor found his little brother playing with a toy knight by the fire, one of Gregor’s toys. Gregor never said a word; he just took Sandor by the neck and held his face in the fire until his skin burned. That is how Sandor got his scarred appearance. Littlefinger suggests not repeating this story to the Hound.

Whilst the tournament is underway, Eddard Stark’s captain guard Jory Cassel announces that the queen has arrived to meet with Eddard in his chambers. Cersei enters and talks to Eddard in private. She suggests putting the unpleasantness from the incident on the Kingsroad behind them. Cersei then asks him what he hopes to accomplish as Hand of the King, and Eddard simply replies to run the realm as best he can for King Robert. Cersei laughs, saying that all they can do is pick up the pieces that Robert leaves behind as the king will simply do whatever he wants to do, and when he wants to do it. Eddard replies that if that is his lot, so be it. Cersei muses that Eddard is just a good soldier, happiest when taking orders. Eddard also says he was trained to kill his enemies. Cersei notes that so was she.

The following day, Cersei visits her husband, telling him she is sorry his "marriage" to Ned Stark did not work out, as Eddard is still unsure of taking the position of Hand. Robert asks if this is the part where she suggests her brother for the job. Cersei replies that Jaime is not serious enough. Robert mentions that one united army behind one leader is worth more than five different armies fighting for different leaders. He adds that the kingdoms’ unity died with the Mad King. Now all the lords want something different: her father Tywin Lannister wants to own the world, Eddard wants to bury his head in the snow, and all he wants is a drink. Robert says that the realm has become a land of backstabbers, money-grubbers and arse-lickers. He doesn’t know what holds it all together. When Cersei replies, "Our marriage," they laugh at the absurdity of it. They share a drink over the idea that hate can hold a marriage together for seventeen years. Cersei unexpectedly asks what Lyanna Stark was like. Robert, surprised, asks why she is asking him now as Cersei explains that at first it was in the hope that if she didn't mention Lyanna, Robert's grief would fade away. She asks now because there is no more damage that Lyanna's ghost could do to them that they haven't already done to each other. Robert tells Cersei that he can't even remember what she looked like, however, Lyanna was the one thing he always wanted, but someone took her away and Seven Kingdoms couldn't fill the hole that was left behind. Cersei tells Robert she did have feelings for him at one point, even after they lost their first child. Cersei asks if it was possible that they could have been more. He hesitates before saying "no", and asks if that makes her feel better or worse. Before exiting his chambers, she replies that it doesn't make her feel anything.

Some time later, beneath a canopy of netting, Eddard Stark is lying on a bed, wounded after being attacked by Jaime Lannister and his men. He sees Cersei and Robert standing by his bed, looking down at him. Cersei asks if he knows of the actions of her brother Tyrion’s abduction and how he dared to lay hands on one of her blood. Eddard replies that his position as Hand gives him the authority to do what he must to keep peace. Cersei retorts to that he is no longer Hand, and now he must face justice himself for his actions. Robert commands both of them to be quiet. He orders Ned to settle his differences with Ser Jaime and get his wife Catelyn to release Tyrion. However, Cersei wants Eddard punished and accuses him of also assaulting  Jaime. Robert, who as her husband should be on her side, will not condemn him without hearing his side and just tells her to be silent. Cersei questions Robert's kingship and manhood. Fed up, Robert strikes her across the face, as a smiling Cersei then informs that she will wear the bruise on her face as a badge of honor. Robert tells her to wear it in silence, or he will honor her again. With one more scathing look at Lord Stark, Cersei leaves the room, slamming the door. Afterwards, much to Cersei’s frustration, Robert leaves the Red Keep to go hunting in the woods outside of the capital and places Eddard in charge in his stead.

Some time later, Cersei meets with Eddard in the gardens of King’s Landing. Ned tells her that he knows the secret that the previous Hand, Jon Arryn, died for: Cersei's three children are not Robert's, but the product of incest between she and her brother Jaime. Cersei does not deny the charge and in fact is proud of it, comparing their love to the old Targaryen practice of marrying brother to sister; she also admits to having despised Robert ever since their wedding night, when Robert drunkenly stumbled into Cersei's bed and called her Ned’s sister’s name "Lyanna". Eddard angrily tells her to take her children and leave the city immediately. When Robert returns from his hunt, he will tell him the truth of the matter and Cersei should run as far as she can before that happens, lest Robert's wrath find her. Cersei icily calls Ned a fool for turning down the throne himself after the sack of King's Landing. Eddard tells her that he has regrets, but that isn't one of them. Cersei departs with a chilling warning: "When you play the game of thrones, you win or you die. There is no middle ground."

Shortly afterwards, Renly Baratheon, King Robert’s younger brother, tears into the Red Keep and finds Eddard to inform him that Robert has been badly mauled by a boar and is not expected to survive. In Robert’s chambers the King telling Joffrey that he wishes he could have been a better father to him, as Cersei looks on with assumed concern of the events. Once Ned and Renly arrive, Robert tells Prince Joffrey to leave so he does not witness his death, to which Joffrey obeys as he frustratedly exits the chambers. As Eddard glances at Robert’s clearly-fatal wound, he’s informed that Robert blames himself as he was drunk during the hunt and missed the thrust upon a wild boar. Robert explains that as he killed the boar in the end he orders the funeral to host the biggest feast the kingdom has ever seen and wants everyone in attendance to taste the boar that killed him. After this statement he commands Cersei, Renly Baratheon, as well as Grand Maester Pycelle and Ser Barristan Selmy from the Kingsguard, to leave him in private to speak with Eddard. After Cersei protests he shouts at her one last time as they all exit his chambers. Cersei learns shortly thereafter that Ned was ordered to write a letter for Robert naming him as the new Lord Protector of the Realm until Joffrey comes of age, although knowing Cersei’s secret, Ned has altered the letter stating “until the rightful heir comes of age” instead of naming Joffrey. However, Ned leaves Robert in his deathbed and chooses not to inform a dying man of his wife Cersei’s deception with regards to their “children”.

Some time after King Robert’s death, Eddard is summoned to the throne room by "King” Joffrey Baratheon. He arrives to find the king’s small council members Petyr Baelish and Lord Varys waiting for him, along with Commander Janos Slynt and a detachment of the City Watch. Lord Varys tells him that Robert’s brother Renly has fled the city, along with Ser Loras Tyrell and a number of retainers, as they fear the Lannister force will be after any of Robert’s family and advisors under a new reign. Varys adds that they were last seen heading south. The party then enters the throne room, where Joffrey sits on the Iron Throne in his finest attire. He demands oaths of fealty from his councilors and subjects. However, Lord Stark instead hands Ser Barristan Selmy the signed proclamation naming him Lord Protector of the Realm. To Ser Barristan's shock, Cersei takes the "paper shield" and tears it up. Cersei then suggests that Eddard bend the knee and swear allegiance. She adds that in return he will be allowed to depart King’s Landing and return to his home in Winterfell. Eddard responds that Joffrey has no claim to the Iron Throne and commands Janos Slynt to take the Queen and her son into custody. However, the City Watch kill all of Eddard's bodyguards and Littlefinger holds a knife to Eddard’s throat, informing him: "I did warn you not to trust me."

Some time after Eddard’s imprisonment under the Red Keep, Cersei and the remainder of the small council, comprising Grand Maester Pycelle, Lord Varys, and Littlefinger, summon Sansa Stark to inform her that her father has been arrested for treason. They manipulate Sansa into writing a letter to her older brother Robb Stark, asking him to bend the knee peacefully to King Joffrey, as he now is the representing the North in his father’s stead. They add that Eddard's fate may depend on his son and the other Northern lords reactions. Sansa begrudgingly agrees to write the letter, however, the plan backfires, as the letter merely encourages Robb to raise an army and march into the Riverlands to confront the Lannister armies directly.

King Joffrey then holds court and appoints Janos Slynt, commander of the City Watch, to be made Lord of Harrenhal as a reward for his loyal service. Cersei then dismisses Ser Barristan Selmy as head of the Kingsguard, noting that the time has come for an honorable retirement. Selmy is confused, pointing out that Kingsguard serve for life, but Joffrey angrily says that Selmy is too old, and wasn't able to protect his father Robert. Selmy's disgrace is only compounded when he learns his post as Lord Commander is to be given to Jaime Lannister, much to his disgust, as he rips off his armor, throws his sword at Joffrey's feet and storms out, stating that he could kill all five of the other Kingsguard present with ease. Sansa then begs Joffrey for her father's life, claiming that the medicine he was taking for his injured leg was responsible for his treasonous talk. Joffrey says that her sweet words have moved him and he will spare Eddard, if he bends the knee to him and acknowledges him as king. Sansa says he will.

The next day, Cersei is present at the Great Sept of Baelor when Eddard Stark “confesses” his crimes, in accordance with the arrangement brokered by Sansa and Lord Varys. Eddard states to the citizens of the capital that Joffrey is the true King on the Iron Throne, appeasing him. Grand Maester Pycelle extols the virtues of mercy as Joffrey then agrees that he could be merciful and send Eddard to the Night's Watch as his mother has suggested and as Sansa has begged for. However, he instead acknowledges that as women they are "soft" and treason must never go unpunished. He commands Ser Ilyn Payne, the royal executioner, to bring him the traitor's head instead. Cersei is visibly horrified when Joffrey arrogantly flouts the arrangement and instead demands Eddard's decapitation. Knowing that this will only lead to another war, she frantically tries to persuade her son to reconsider, but the order is nonetheless carried out by Ilyn Payne. The crowd goes into an uproar and Sansa screams as she is restrained by guards. Forced to kneel, Eddard looks onwards in the crowd to see his other daughter Arya Stark witnessing in horror. Ser Ilyn draws Eddard's own sword and cuts his head off with a single blow. A flock of pigeons take flight immediately afterwards over the cheering crowd of King’s Landing.

Sure enough, war eventually erupts between the Lannister and Stark armies in the Riverlands. King Joffrey is holding court and a singer named Marillion is brought before him, charged with making up an offensive song about the late King Robert and Cersei. The song says that the boar might have killed the king, but the “lion” in his bed had previously castrated him. Drunk on new-found power, Joffrey asks Marillion, if he wants to keep his hands or tongue. Marillion fearfully responds that everyone needs hands. Joffrey commands Ilyn Payne to cut out his tongue instead. Later that evening, Cersei is in her bed chambers and has taken a new lover, her cousin Lancel Lannister, who was King Robert's squire. She receives a letter informing her of her brother Jaime's capture by Robb Stark in the Riverlands. Lancel asks for the news of the war and asks what their next move is, but Cersei tells him to shut up and get back in bed.

Some weeks later, Cersei continues to govern from King's Landing as the Queen Regent to her son, King Joffrey Baratheon. She is driven to defend Joffrey's claim in the face of several challengers in the War of the Five Kings. Facing imminent winter, she orders the city gates barred to prevent further refugees from entering the city. She is perturbed by the arrival of her brother Tyrion, who has been named acting Hand of the King by their father, Tywin Lannister. She fears that Tyrion schemes to usurp her power and is frustrated when he tells her that since she failed to prevent the death of Eddard Stark, she has been viewed as the disappointing child by Tywin and is blamed for the execution and the resulting rebellion in the North. Cersei claims that she tried to stop it and Tyrion counters that she failed and because of that, the consequences will haunt the Lannisters for an entire generation. Tyrion then wins her temporary acceptance when he pledges to free their brother Jaime from Robb Stark’s captivity in the Riverlands, but insists that they need to find the missing Arya Stark in order to facilitate a prisoner exchange.

Cersei later requests Petyr Baelish to assist in finding the fugitive Stark girl. Littlefinger suggests that she will return to Winterfell if she has escaped, as Cersei informs that Arya will be valuable should they choose to negotiate with House Stark, also reminding Baelish that a Lannister always pays their debts. Cersei fingers the Mockingbird clasp of his coat and notes that he created his own sigil and says his choice was appropriate for a self-made man with many songs to sing. He responds by saying that some people are not born into the right families and must find their own way. Cersei informs that she has heard a song about a poor boy that fell in love with a lord's daughter. She adds that the daughter had eyes for another, referring to Petyr’s own childhood with House Tully, his feelings for Lady Catelyn Stark and her preference for Brandon Stark over Petyr himself. He retorts that boys and girls living together can lead to awkward situations, even between brother and sister and adds that such relationships becoming common knowledge is an awkward situation for a prominent family. Cersei takes his bait and he tells her that knowledge is power. She orders her men to seize him and cut his throat and then pretends to change her mind. She orders the men to step back, turn around and close their eyes, demonstrating her control. She tells Littlefinger that “power is power” and repeats her request to look for Arya, telling him to take time away from his coins and whores.

Afterwards, Cersei enters the throne room to find it being redecorated. She asks King Joffrey what he is doing and he informs her that he is restoring the proper appearance of the room to match the throne. Cersei tells Joffrey that they need to find Arya in order to exchange both her and Sansa Stark in return for Jaime, whom Joffrey doesn’t believe is his real father. The young king insists his belief that the Starks are weak enough to trade Jaime for Sansa alone, claiming that they overvalue their women. Cersei then suggests they set their armies to search for Arya and ask Tywin for aid, however, Joffrey asserts that a king doesn’t ask but commands his subjects. Cersei urges that Jaime’s life is in danger as Joffrey counters that while they are at war all of their lives are in danger. He brings up the rumors about Cersei’s incestuous relationship with Jaime. She responds that their enemies will say anything to weaken his claim. He is annoyed at her calling it a claim, saying that the throne is his. She agrees with him and tells him that no-one believes the gossip. Joffrey insists that someone believes it, questioning Cersei about the late King Robert’s other children. She wonders why he is asking about Robert’s bastards. He coarsely restates his question as Cersei then slaps him. He warns her that her action is punishable by death and tells her never to strike him again.

Some time later, Cersei reads Robb Stark's peace terms aloud to the small council before tearing them up, which requests the return of Sansa, Arya and Eddard Stark’s remains as well as demanding Northern independence from the Seven Kingdoms. Tyrion tells her that she has perfected the art of tearing up papers and suggests that they at least return Lord Eddard’s remains as a gesture of good faith. Cersei asks the messenger Alton Lannister to deliver their reply and to tell her brother Jaime that he has not been forgotten. Grand Maester Pycelle reports a raven from Castle Black and gives its message to Tyrion but Lord Varys interjects that the wildlings are becoming increasingly troublesome and adds that the wildlings are organizing behind the King beyond the Wall Mance Rayder. Cersei jokes that she has lost track of the number of kings as Tyrion says that the message is from the Lord Commander of the Night’s Watch and that he is asking for more men. Cersei says that they cannot spare any because they are fighting their own war. Tyrion reads a troubling passage: “the cold winds are rising, and the dead rise with them.” Pycelle dismisses it as northern superstition and Cersei makes to leave. Tyrion relays Jeor Mormont's encounter with a wight and asserts his reliability. Cersei mocks Tyrion as having become gullible as he retorts that he is not sure what he believes but reminds her that the Night's Watch is the only thing that separates them from what lies beyond the Wall.

That evening in Tyrion’s chambers Cersei rages that he did not have the authority to replace Janos Slynt of the City Watch. He asserts that his position as Hand of the King gave him the right and warns her that she is losing the people. As she is disinterested in the feelings of her people he then warns her that she might find it difficult to rule a populace who want her dead. He predicts that the people will turn against her in the winter and that the slaughter of Robert's children has given them a rallying cry. He is surprised at the lack of a denial and then concludes that Joffrey gave the order without Cersei's knowledge. She says Joffrey did what he had to and characterizes ruling as “lying on a bed of weeds, ripping them out one by one before they strangle you in your sleep.” Tyrion retorts that there is more to ruling. Cersei shouts that she doesn't care what he thinks and complains that ruling has always fallen on her because her brothers did not take it seriously. Tyrion jokes that Stannis is claiming that Jaime has done the same repeatedly. Cersei pauses and then says that Tyrion is funny. She says that none of his jokes will ever match him killing their mother, Joanna Lannister, as she gave birth to him. Tyrion points out that she was his mother too. Cersei says that her mother being gone for the sake of Tyrion is the biggest joke in the world. She leaves Tyrion to consider her words.

Some days later, Cersei hosts an awkward dinner for her children Tommen and Myrcella as well as her captive Sansa Stark. Myrcella asks when Sansa and King Joffrey Baratheon will wed and Cersei tells her that it will be after the war. Myrcella then remarks on the new dress she will have made for the day and then informs that Sansa's will be ivory as she is the bride. Cersei then prompts a silent Sansa to respond as Sansa apologizes and assures Myrcella that her dress will be beautiful. Sansa then summons her usual line of forced devotion to King Joffrey and then asserts, as convincing a performance as she can muster, her “eagerness” for the war to finish so she can be wed to the king. Cersei, however, understands what it means to be in an arranged marriage and allows Sansa to continue peddling her dishonesty towards her son. Tommen then asks if Joffrey is going to kill Sansa's brother Robb Stark. Cersei asserts that Joffrey might and asks if Tommen wants him to. Tommen says that he does not as Cersei insists that if Joffrey does Sansa will do her duty anyway. Sansa chokes down her helpless anger as her eyes fill with tears.

After his meetings, Tyrion enters his chambers to find Cersei waiting for him, who is irate about his new marriage plans for Myrcella. Cersei says that she will not allow Myrcella to be shipped to Dorne, similarly to how she was sent to King Robert. Tyrion asserts to his sister that Dorne will be the safest place for her, adding that they must seduce the Martells into an alliance and that the support of Dorne could win them the war that Joffrey started. Cersei worries that her daughter will be a hostage and Tyrion counters that she will be a guest. Cersei threatens Tyrion, saying that the letter from their father Tywin that appointed him as Hand is a mere piece of paper, and offers no protection. Tyrion asserts that Cersei cannot stop the plan now that it is in motion as she becomes hysterical, smashing glasses from his table. Tyrion cautions her that Myrcella would be in grave danger if King's Landing was sacked, demanding to know if Cersei wants to see her daughter raped and murdered like the children of House Targaryen during the Sack of King's Landing; Tyrion promises Cersei that if the city falls, they will put Myrcella's pretty little head on a spike next to hers. Cersei tells him to get out and shoves him over before sinking into a chair. He leaves her alone in his chambers.

Some time later, Cersei watches her daughter Myrcella from behind a stone lattice on a balcony as Tyrion joins her to deliver the news of Renly Baratheon’s murder. He reports there are varying accounts of who is responsible and elaborates that some say Catelyn Stark was responsible and others say that it was King Robert’s other brother Stannis Baratheon himself. Tyrion warns her that Renly’s armies are joining Stannis, who will have superiority over them on both land and sea with the addition of Renly’s banners. He also warns that Stannis will strike against them sooner rather than later. Cersei attempts to change the subject, asking if Tyrion should be doing something else like sealing Myrcella in a crate so that she can be shipped away. Tyrion responds that his niece will be safer in Dorne. Cersei sarcastically notes Tyrion’s concern for Myrcella’s safety. Cersei says that Tyrion is so clever with his schemes and plots and moves inside from the balcony. He returns the discussion to the pressing threat of attack and their need to ready King’s Landing for assault. Cersei says that Tyrion need not concern himself over it and that Joffrey is preparing the siege preparations personally. Tyrion asks for specifics and Cersei refuses to discuss it. He says that it is important that they talk about it and she again refuses, citing the King’s need for secrecy.

Days later, Princess Myrcella is rowed away from the docks of King’s Landing to a ship waiting at anchor. Her departure is watched by Cersei and Tyrion. The High Septon prays for a safe journey for her. Myrcella sobs as the boat moves further away from her family. Cersei tells Tyrion that she hopes that he will one day truly love someone so that she can inflict the same pain of taking them away from him. Tyrion looks pointedly at his sister before walking away. Upon re-entering the city, Joffrey is met by an unruly crowd of peasants. Cersei follows behind and her attention is caught by the jeering crowd. The people call out to King Joffrey for food as he is struck in the face by thrown cow excrement. The crowd begins to riot, attacking the guards with rocks. Cersei and Tyrion are each defended by Lannister guardsmen and Tyrion urges his sister onwards. Sandor Clegane grabs his king and pulls him through the mob. Joffrey asks what they are doing and repeats his order to execute the people. Sandor explains that the rioters want the same for Joffrey. The High Septon is overwhelmed by the mob and is torn to pieces. Sandor then hands off Joffrey to one of his sworn brothers to fight the rioters. The Kingsguard kill several rioters as they drag Joffrey to safety behind a gate. The Kingsguard push Joffrey, Cersei and Tyrion inside and turn to defend the entrance.

Some time later, Sansa is summoned to Cersei’s chambers after a stressful reaction over her first period. She tells Sansa that she is now a woman and asks if she understands the implications. Sansa responds that she is fit to bear children for the king. Cersei senses her trepidation but reminds her that it is the greatest honor for a queen and then reveals that she was in labor for a day and a half during Joffrey’s birth. After recalling the birth Sansa wonders why King Robert was not with her and Cersei explains that he was hunting but elucidates that she didn't want him there and was content with Pycelle, midwives and her brother Jaime. Cersei predicts that Joffrey will show Sansa no devotion during birth but reassures her that while she may not love the king, she will love their children. Sansa says that she loves Joffrey with all her heart. Cersei calls the lie touching and asks Sansa to listen to some womanly wisdom. She assets that the more people you love the weaker you are as it leads to obligations. Cersei then admonishes Sansa to love no-one but her children because a mother has no choice. Sansa asks if she should love Joffrey. Cersei responds that she can try, calling her “Little Dove.”

That evening, Tyrion reports the latest news, stating Stannis’ fleet has been spotted sailing north past Tarth with 200 ships and will reach the city within five days. He then asserts that Joffrey needs to start acting like a king, warning that the war Cersei started is coming to their doorstep and the city wants Joffrey dead. Cersei quietly admits that she hoped that her son would be like Jaime. She says that he looks like Jaime in a certain light. Tyrion observes that he is more like Robert than Jaime. Cersei says that Robert was a drunken fool but did not enjoy cruelty. Tyrion has no response and fidgets in his seat. Cersei goes on to wonder if Joffrey’s cruelty is the price she must pay for her sins. Tyrion tries to comfort her that the Targaryen’s practiced incest for centuries. She says that Jaime and her used to console each other with the same fact when they had doubts. She recalls using the same defense when Eddard Stark confronted her with evidence of her incest. She reveals that she does not believe it absolves her because of the madness that plagues the Targaryen bloodline, repeating the common saying that when a Targaryen is born the gods flip a coin to predict their sanity. Tyrion says that Cersei has beaten the odds because Tommen and Myrcella are good decent children. Cersei begins to cry and Tyrion approaches her but cannot bring himself to comfort her.

Some days later, Cersei and Tyrion have dinner in her bedchamber. After learning that Joffrey is keen to fight in defense of the city, Cersei is furious as Tyrion calls it an inspiration for their troops. Tyrion also notes that there are boys younger than Joffrey that will be fighting Stannis’ force. She reminds him that he sent Myrcella to Dorne and then accuses him of wanting to send Joffrey to die, however, Tyrion insists that Joffrey needs to be on the battlefield because the men will fight better if they can see their king fighting beside them. He insists that Joffrey must fight instead of hiding behind Cersei’s skirts. With this Cersei then chooses to reveal that she has captured his whore. She teases that Tyrion’s lover is beautiful, complimenting her body then adding that the bruises she has inflicted will heal with time. Tyrion asks where Cersei found her as she criticizes him for giving her a Lannister lion necklace. As Tyrion attempts to keep his emotions from escalating, a bruised Ros, whom Tyrion first met at Winterfell, is forcefully escorted into the room. Unbeknownst to Cersei she has the wrong girl, but Tyrion plays his reaction as if she does in order to protect his actual lover from being found. Tyrion vows to free Ros and after she is taken away, he turns around and glares hatefully at Cersei. He growls that he will hurt her for what she has done, swearing that at a time when she thinks she is safe and happy he will “turn her joy to ashes in her mouth and that she will know the debt is paid.”

Some time later, as Stannis’ fleet is hours away from King’s Landing, Grand Maester Pycelle is summoned to see Cersei in her chambers. He informs her that it is his duty not just to serve the royal house but also to offer guidance in times of conflict. Cersei impatiently asserts to him that his words are always wise and measured. She then begins to prompt him but he interrupts to say that a maester’s duties become more urgent in war time. He begins to reminisce and Cersei interrupts to ask if he has brought what she asked for. Pycelle confirms that he has and hands her a small bottle of Essence of Nightshade. He warns that it is as dangerous as it is efficacious and then explains that a single drop can cause relaxation, three drops a deep sleep and begins to explain what ten drops will do. Cersei interrupts him to say that she already knows. Pycelle asks permission for a question as Cersei curtly denies it. She says that he must be busy preparing for the battle. Cersei then warns him to take care as he descends the many stairs on his way out.

After Stannis’ arrival with his fleet the Battle of the Blackwater is underway. While King Joffrey and Tyrion lead the battle outside, Cersei provides refuge for the women and children of the court in a room within Maegor's Holdfast, a fortress inside of the Red Keep. With Tommen by her side she prepares for the worst by having the executioner Ser Ilyn Payne present as well as the deadly Essence of Nightshade poison from Pycelle. Cersei drinks wine heavily during the assault and seems to simultaneously torment and mother Sansa Stark with matter-of-fact descriptions of the rapes that will occur if the city falls, among other pessimistic musings. She then tells Sansa that the gods have no mercy and that Ser Ilyn is there to kill them should the Red Keep be breached. Afterwards, Cersei begins to question Sansa’s handmaiden Shae, whom is Tyrion’s secret lover. Cersei seems to think that Shae is perhaps an unlikely handmaiden to Sansa. After several more glasses of wine, a wounded Lancel Lannister returns from the battle to report that Stannis Bartaheon has reached the Mud Gate, despite Tyrion's ingenious use of wildfire to destroy a large portion of his fleet. Cersei then commands Lancel to bring Joffrey back to the Red Keep, ignoring his protests that it will damage morale. It is later reported by Lancel that Joffrey willingly left the field but his exit is a blow to the men. Lancel begs Cersei to let him return the king to the front, believing the battle is lost otherwise. Cersei pushes him into a stone pillar, aggravating his injury, and storms out, leaving Sansa alone to deal with the frightened women who are increasingly losing hope of a win.

As the battle continues, a terrified Cersei sits on the Iron Throne holding Tommen on her knee. She offers to tell him a story in an effort to remain calm about a mother lion and a cub who lived in the woods. Cersei says that the mother loved her cub but that there were evil things like wolves that lived in the woods. She adds that the lions could hear them howling in the night and the cub was frightened but the lioness reminded her cub that he was a lion and told him not to be afraid. Cersei then says that one day all the beasts will bow to the lion cub and that he will be king. “The stags, the wolves, the bears in the north, the foxes in the south, the birds in the sky and the beasts in the sea will come to him to rest a crown upon his head.” As Cersei then uncaps the poisoned bottle of Essence of Nightshade, all hope lost, she tells Tommen that the lioness informed the cub that he would be strong and fierce just like his father. Cersei then puts the bottle in Tommen’s hand and promises to keep him safe. As Cersei is about to give the poison to her young son, Ser Loras Tyrell, who previously associated with the late Renly Baratheon, bursts into the room with his soldiers. He rides in with Tywin Lannister, who finally has returned to King’s Landing, along with the combined army of House Lannister and House Tyrell. Her father pushes through the crowd and into the throne room as Cersei pours the Essence of Nightshade onto the flagstones and dropping the bottle to a shatter. Lord Tywin then announces that the battle is over and they have won. A relieved Cersei hugs Tommen close to her body.

Following the battle, her brother Tyrion's important role in defending the city is not acknowledged and he is left to recover from his wounds, stripped of his power and title as Hand of the King. Rumors also circulate that Cersei ordered an attack on Tyrion at the hands of a Lannister knight named Ser Mandon Moore. No longer considering Tyrion a threat, Cersei releases “his lover” Ros back to Littlefinger’s brothel. King Joffrey and Cersei then orchestrate a public ceremony rewarding those who aided the city in the battle. Tywin Lannister is officially recognized as the new Hand of the King as Petyr Baelish is named Lord of Harrenhal for brokering the alliance with House Tyrell. Ser Loras Tyrell is then offered a favor of his choosing. He asks Joffrey to marry his sister, Margaery Tyrell, who was prevously betrothed to Renly Baratheon. Joffrey says that he is constrained by his betrothal to Sansa Stark, however, Cersei intervenes to insist that the treachery of House Stark frees him from any obligation. The court welcome the decision with a round of applause, as House Tyrell replaces House Stark in allegiance with the crown.

Some weeks following the Battle of Blackwater, Cersei Lannister pays her brother Tyrion a visit in his chambers, accompanied by two of Joffrey’s Kingsguard. She only gains entrance to Tyrion's chambers after agreeing to leave her guards outside. Once inside Cersei demands to know how he will "slander" her to Lord Tywin now that their father has returned. Tyrion asks when he has ever slandered her before, and she reminds him of a time at Casterly Rock that he got her in serious trouble with their father: when she was nine years old, Cersei discovered that a servant girl, also nine years old, had stolen a necklace, so she had her guards beat the girl, who ended up losing an eye. Tyrion told their father what Cersei had done and he was angered, but Cersei notes that the servant girl never stole a necklace again. Tyrion quips that it isn't "slander" if it's true, and he only told Tywin what she really did. The queen admits that Tyrion is a clever man but not as clever as he might believe. Tyrion merely retorts that this still makes him a great deal more clever that her.

Later that evening, Cersei and Joffrey host a private dinner party for Lady Margaery and Ser Loras Tyrell. Maragery remains polite despite a few barbs thrown at her by Cersei with regards to her dress, or lack-there-of. Cersei then makes a few disparaging remarks about Margaery's visit to the slums of Flea Bottom, as she is surprised that Margaery has been handing out food to the smallfolk of the city as well as visiting orphanages. Margaery deflects such comments, getting unexpected support from King Joffrey, much to Cersei's annoyance. Unlike Cersei, who only knows how to rule through fear, Margaery is skilled at winning the hearts and minds of the common people, and this concerns Cersei. Margaery is also pleased to hear that hundreds of wagons stuffed with food and supplies are arriving daily from the Reach, provided by House Tyrell in order to aid the capital. After trading veiled insults with both her son and future daughter-in-law, it becomes clear that Cersei doesn't trust Margaery and fears that the younger woman has come to usurp her as queen.

Later on, Joffrey is being fitted for new clothes in his chambers, in preparation for his upcoming wedding to Margaery. Cersei begins to criticize Margaery, saying that she is only charitable to the poor to build up support for herself, and also saying that she thinks she dresses like a harlot. However, Joffrey barely tolerates his mother's chiding and dismissively tells her off.

Some days later, Tywin Lannister calls the first meeting of the small council since he arrived in the city and assumed his position as Hand of the King. He has the meeting place changed to a room next to his own quarters in the Tower of the Hand, asserting his dominance. Tywin arrives early and arranges the chairs on one side of the table, away from his own, as a test to see how each council member will respond to seating arrangements. Petyr Baelish immediately grabs a chair and moves it closest to Tywin, displaying his eagerness, followed by Lord Varys and Pycelle. Cersei then arrives and pointedly pulls up a chair so she is sitting at Tywin's right hand, opposite Littlefinger. Tyrion, however, dramatically drags his chair as far away from Tywin and the rest of the council as possible. After discussing Jaime Lannister’s unknown whereabouts, Tywin commands Baelish to travel to the Vale and use his connection to Lysa Arryn to secure an alliance with House Arryn. Tywin then reveals that he has appointed Tyrion as the new Master of Coin to replace Baelish. While this may seem like giving Tyrion a position of relative power again, Tyrion quickly points out that he has no prior experience in finance. With backhanded compliments, a gloating Cersei makes it clear that this promotion is really intended to give him an opportunity to make mistakes he will later be blamed for.

Some days later, King Joffrey gives Lady Margaery a tour of the Great Sept of Baelor, where their royal wedding is to be held in a few weeks time, as Cersei and the matriarch of House Tyrell, Lady Olenna trail behind. Joffrey excitedly relates tales of the darker chapters of the Great Sept's history, to Margaery's feigned interest and Cersei's annoyance. Olenna asks if the late King Robert was buried with the Targaryen kings in the Great Sept as Cersei then explains that he left instructions to return his remains to Storm's End, the historical seat of House Baratheon. When Cersei dismisses the accident that claimed Robert's life, Olenna laments her son's total lack of military prowess. Cersei points out that Olenna's son Lord Mace Tyrell besieged Storm's End for almost a full year during Robert's Rebellion, but Olenna scoffs that her oaf of a son is no warrior and the only thing he laid siege to was the banquet table in the command tent. Olenna muses on the shortcomings of the men in their lives and the arrangement of patriarchy in general, to which Cersei wistfully says that it is the will of the gods. Thus distracted, Margaery convinces Joffrey to greet the crowd outside on the steps of Baelor. Having been somewhat placated by Margaery's charity, the crowd happily cheers for the pair of them. Cersei realizes she has lost control of Joffrey to the Tyrells.

Subsequently, Cersei then meets with her father Lord Tywin in his chambers as she wants to ensure that he is doing everything he can to find her brother Jaime. Tywin dismissively points out that he started a war when his hated dwarf son Tyrion was captured by the Starks, so assuredly he is willing to do even more now for his elder son. Tywin makes it clear that he considers Jaime his heir as Cersei points out that as she is next in line of succession maybe Tywin should consider her the real heir to his legacy, not his sons. She claims she is the only one of his children who ever took his lectures on family and legacy seriously. Tywin confirms that he excludes Cersei from his plans, but not because she is a woman: he distrusts her because she isn't nearly as smart as she thinks she is. He sneers that she has allowed Joffrey to run roughshod over her and the city and he intends to rein in his grandson's deranged behavior. Cersei says she is afraid of the growing influence of the Tyrells at court, and something must be done about them. In particular, Cersei is nervous about how skilled Margaery is at manipulating Joffrey. Tywin bluntly responds that it's good someone has finally been able to manipulate Joffrey, as Cersei herself has clearly proven to be incapable of doing it. She says Tywin should try stopping Joffrey from doing what he likes her father firmly responds, "I will."

Some time later, Cersei encounters Lord Baelish and informs him that she fears the Tyrells do not have the Lannisters' best interest at heart. Littlefinger agrees that he will use his spies to uncover their plans, one of which turns out to be marrying Ser Loras Tyrell to Sansa Stark. Afterwards, Cersei meets with Tywin and Tyrion to report this development. Initially, Cersei is delighted when her father decides to "kill this union in its crib" by instead having Tyrion marry Sansa to secure the North. However, her smug attitude when this is revealed to Tyrion quickly evaporates when Tywin then announces his intention to have her marry Ser Loras to secure the Reach. Cersei protests against this, asserting that she is Queen Regent and not some broodmare, however, Tywin angrily declares that she is his daughter and she will do what he tells her, adding that this arrangement would put an end to the incestuous rumors about her and Jaime. Cersei begs Tywin not to make her enter another loveless marriage but he refuses to hear another word from either of his children, saying they have disgraced the family name for far too long. As Tywin leaves the room, Cersei and Tyrion both glumly contemplate their new marriage arrangements, which would also not be welcomed by either Sansa or Ser Loras.

Days later, as Ser Loras and Sansa discuss their impending nuptials, Tyrion and Cersei observe the couple from Cersei's chambers overlooking the garden. Tyrion sarcastically asks which of the four of them has it the worst. He then finally accuses his sister of trying to have him killed during the Battle of the Blackwater. Cersei, tired of fighting him, remains quiet while he deduces that while Cersei certainly has the authority to command a Kingsguard, she isn't stupid enough to command Ser Mandon Moore to kill him in public. Tyrion realizes that it was in fact Joffrey who ordered Mandon to kill him, because Tyrion is the only one who has ever stood up to the young king. Cersei tells him his life is not in danger from Joffrey, as he dare not try anything like that now that Tywin is the Hand. They discuss about Jaime's possible return to King's Landing, with Cersei wondering where he could possibly be. She asks Tyrion which one of them should be the one to break the news to Sansa. Tyrion decides he might as well dash Sansa's hopes sooner rather than later. He goes to Sansa's chamber, who is with his lover Shae. Tyrion asks for a private word, but Sansa declines to dismiss Shae. Tyrion then gives Shae a carefully coded apology for not telling her in private before breaking the news to Sansa.

Some weeks following, on the day of Tyrion and Sansa’s wedding, everyone gathers inside the Great Sept of Baelor. Lady Margaery tries to ingratiate herself to Cersei, commenting they will technically be sisters soon. Cersei responds by telling Margaery the story behind the "Rains of Castamere," relating how it refers to the destruction of House Reyne of Castamere after their failed rebellion against House Lannister. The story implies similarities between the ambitions and position of Houses Reyne and House Tyrell and that the same fate may fall upon the Tyrells if they plot against the Lannisters. Cersei concludes by threatening to have Margaery strangled in her sleep if she ever dares call her sister again. The ceremony is a grim affair; Joffrey smugly escorts Sansa to the altar in place of her father and petulantly removes the stool upon which Tyrion was to stand on to cloak Sansa in Lannister colors as part of the ceremony, eliciting snickers from the congregation, though the scowl of Lord Tywin quickly silences them. Tyrion in the face of humiliation asks Sansa to kneel and he places the cloak around her shoulders. The new High Septon begins the ceremony.

That evening, as man and wife, Tyrion and Sansa have their reception dinner, which also proves a grim and miserable affair. Tyrion spends the wedding feast mostly by getting deeply drunk and making light of his father's insistence that his inebriated state will render him unfit to impregnate his wife. At the same time, King Joffrey is himself drinking too much wine, and losing what few inhibitions he has, his behavior becomes increasingly offensive to both Sansa and Tyrion. Against Cersei's ineffectual protests, Joffrey gets up and, flanked by his Kingsguard, taunts Sansa that she's still found a way to marry a Lannister. Joffrey then reflects that it doesn't matter which Lannister gets her pregnant, and openly says he might want to rape her after Tyrion is done with her, while the Kingsguard hold her down. Cersei then retreats to an upper gallery and stares despondently out over Blackwater Bay. Ser Loras finds her and tries to make small talk, an attempt to break the ice over their impending marriage. Cersei, however, rudely brushes him off. Joffrey then declares it time for the bedding  ceremony, which involves the bride and groom stripping off before being carried to their marriage bed. When the drunk Tyrion angrily insists there will be no bedding ceremony and slams his dagger into the table. He threatens that Joffrey will "be fucking [his] own bride with a wooden cock" if he doesn't let it drop. As the court stands in shocked silence, Joffrey seethes with outrage and Tyrion defiantly glares at his nephew with pure hatred. After tensions subside, Tyrion and Sansa leave the feast.

Some days later, in Tywin's chambers Joffrey jubilantly informs the council of Robb and Catelyn Stark’s deaths at the hands of Lord Walder Frey during the Red Wedding massacre. King Joffrey gleefully states that he intends to serve Robb's severed head to Sansa at his wedding feast. None of the small council are able to mask how distasteful they find the concept. Varys points out that Sansa is Joffrey's aunt by marriage now, and it would be unseemly not to give her the basic respect that accords. A deeply embarrassed Cersei forces a smile and insists to the rest of the council that Joffrey was only joking and did not mean it. This puzzles Joffrey, who matter-of-factly states to his mother that he did mean it. Tyrion flatly forbids it and tells Joffrey that Sansa isn't his to torment anymore. Joffrey angrily proclaims that he is the king, and everyone is his to torment. Lord Tywin counters that any man who has to remind his subjects that he is king, is no true king. Joffrey goes apoplectic and tries to fight his grandfather, deriding Tywin as a coward who hid under Casterly Rock while King Robert won the real war when he overthrew the Targaryens. The entire small council tenses waiting for Tywin to respond to this shocking insult: instead Tywin coldly and calmly declares that the king is tired and advises Cersei to see him to bed. Joffrey weakly protests that he is not tired, however, he leaves with his mother as Tywin asks Pycelle to give his grandson a sedative to make sure he goes to sleep.

That evening, Cersei visits Tyrion and rudely dismisses his squire, Podrick Payne. Cersei informs Tyrion that he should give Sansa a son if he truly wants to make her happy, though Tyrion responds by asking her if she is happy as she has children. Cersei admits that she is not happy, but would've thrown herself "from the highest window in the Red Keep" without them, even Joffrey. She recounts of how he was all she had before Myrcella was born and how she would spend hours looking at him, and acknowledges that he is one of the "terrible ones". Tyrion asks her when this will end, and Cersei replies when they have dealt with all their enemies. Tyrion mentions how dealing with one enemy creates two more, and she just says that they will be in this position for quite some time. The following morning, Cersei reminices in her chambers over sentimental keepsakes. She fondly stares at a seashell on her bed while recalling her youth on the shores of Casterly Rock. Cersei is then interrupted as she turns around upon hearing her name called out by her brother Jaime, who has finally returned to the capital. She is visibly relieved that Jaime is alive but shocked to find him maimed, as he now is missing a hand.

Some time after Jaime’s return to the capital, Cersei and Jaime have summoned Qyburn, a former maester of the Citadel, who Jaime met on the road back to King’s Landing. Qyburn was thrown out of the Citadel and removed of his title as maester for conducting illegal human experimentation. As someone who was able to treat Jaime’s arm when his hand was cut off, Qyburn is requested by Cersei to attach a golden prosthetic hand made for Jaime to his stump. Qyburn asks Cersei about her symptoms, and she says they are gone. After Qyburn departs, Jaime questions what symptoms she was referring to that needed assistance from the former maester but she tells him they are not of his concern. Jaime then informs her that he will stay in the Kingsguard with one hand so he can stay close to her before asking why she drinks more than she used to. Cersei replies that she drinks more because Jaime left the capital, King Robert  was killed, Myrcella was shipped off to Dorne, they suffered through a siege and her son is being married to Lady Margaery, whom she despises. Cersei then informs him that everything has changed and that he took too long to return and implies that she has taken other lovers and that their relationship has changed because of his lengthy absence, a statement that clearly wounds Jaime. Suddenly, Bernadette, a Red Keep handmaiden, enters to inform Cersei that she has seen Sansa’s handmaiden Shae leaving her brother Tyrion’s chambers.

On the morning of King Joffrey and Lady Margaery’s wedding, a breakfast is held. Mace Tyrell, gifts Joffrey a magnificent golden chalice with seven facets, one for each of the major houses in the Seven Kingdoms and wishes him and his daughter Margaery a long and happy marriage. Joffrey graciously accepts. Cersei then spots Sansa’s handmaiden Shae and informs Lord Tywin that she is Tyrion's whore, as he then commands for her to be sent to the Tower of the Hand before the wedding. Tyrion overhears this and looks vexed, but proceeds to approach Joffrey and presents him with the “Lives of Four Kings,” a book detailing the reigns of four kings by Grand Maester Kaeth. Joffrey accepts the gift, but his sincerity seems questionable. A member of the Kingsguard then presents a Valyrian steel sword and Tywin tells him that it is one of two swords of its kind in the capital, as Joffrey excitedly rushes to wield it. He promptly begins to slash at Tyrion's gift despite its rarity, and then asks for suggestions on its name from guests in attendance. He settles on the name “Widow's Wail”.

That afternoon, King Joffrey and Queen Margaery's wedding ceremony takes place in the Great Sept of Baelor conducted by the High Septon and they are wed in front of gods and men. After the ceremony, the royals gather outside the Red Keep for a lavish wedding feast in celebration of the union of House Lannister and House Tyrell. Cersei is sitting with the rest of the royal family when Brienne of Tarth approaches the King and Queen. Brienne bows and congratulates them on their marriage. Cersei quickly points out that she bowed instead of performing a curtsy. She then thanks Brienne for bringing her brother back and abruptly asks her if she loves Jaime. Brienne responds by walking off. After Margaery announces to the court that the leftovers are going to the poor, Cersei kisses her on the cheek and says she is an inspiration to them all. Shortly after, she instructs Pycelle to go to the kitchens and order the cooks to give the leftovers to the dogs instead. Pycelle is reluctant to do so, but Cersei threatens to have him killed if he does not. Cersei and Tywin then meet Prince Oberyn Martell and Ellaria Sand, who are visiting from Dorne, and the four get into a heated discussion when Cersei hypocritically mocks Ellaria's baseborn origins despite the fact that her own children are also bastards and born out of incest no less. The tension is interrupted as five dwarves then ride out from a large lion’s mouth, representing Joffrey, Renly Baratheon, Stannis Baratheon, Robb Stark, and Balon Greyjoy, each of the five kings in the War of the Five Kings. After an insulting jousting performance that mocks each kings sans Joffrey himself, Joffrey then makes his speech and publicly embarrasses Tyrion, much to Cersei's delight. After Tyrion outwits him in front of all his wedding guests, Joffrey petulantly pours wine over Tyrion's head and orders him to serve him wine as his cupbearer. After a few sips Joffrey then begins to choke on his wine, causing him to gasp for air and collapse. Joffrey tries to speak, but begins coughing. He grabs his throat, as Margaery and Olenna Tyrell exclaim that he is choking and needs help. After collapsing face down and vomiting, Jaime and Cersei rush in and turn Joffrey over on his back. Dontos Hollard, a King’s Landing jester, suddenly approaches Sansa Stark from behind and says she must come with him quickly, as they flee the scene.  Joffrey then dies in his mother’s arms, blood flowing from his eyes and mouth from the effects of the strangling poison. In a blind rage, Cersei accuses Tyrion and has him arrested. Upon noticing that Sansa has vanished, she immediately begins to suspect her too and petulantly demands to know her whereabouts. As Tyrion is seized and sent to the cells of the Red Keep, Tywin orders the Kingsguard to bar the gates of the city and seize every ship in the harbor as no one is allowed to leave the capital.

Some time later, after Joffrey’s funeral in the Great Sept of Baelor, Cersei is mourning over her son’s body. Lord Tywin arrives and wastes no time in prepping young Tommen for the inevitability of his coronation as the new King of the Seven Kingdoms. After informing his grandson that he has the right temperament for a ruler, Tywin immediately begins instructing Tommen on the qualities of a good king, much to Cersei’s annoyance. Perhaps all-too-insensitively, over his dead body, Tywin explains to Tommen that Joffrey was not a wise king. After the two leave, Jaime arrives to comfort Cersei. She breaks down into tears and asks Jaime to avenge their son by killing Tyrion. Jaime is not convinced that Tyrion was behind the murder and tells Cersei that there will be a trial, but she does not care. He tries to comfort her through his affections. Cersei refuses initially, but Jaime is aggressive. Cersei insists that the sept during a private viewing of their son's corpse is a highly inappropriate place for sex, and asks Jaime to stop, insisting that "It isn't right." Jaime, however, refuses to stop, asserting that he doesn’t care. Cersei eventually gives in and the pair engage in angry sex on the floor next to Joffrey's corpse.

Days later, Cersei calls upon Jaime, however, only to enquire about Kingsguard formations for protecting Tommen. She then scolds Jaime after learning there is currently only one guard protecting the young successor, as Jaime assures her that Tommen is safe. Cersei then ponders as to why Catelyn Stark released him from his captivity several months ago. Jaime replies that he swore by the gods that he would bring Lady Catelyn's daughters back to her. Cersei questions his loyalty to their enemies, but Jaime states that he only did it so he could return to her in the capital. She then questions his oath to Catelyn and venomously asks what would he do if she asked him to track down and kill the “murderous little bitch” Sansa Stark, believing that she schemed with Tyrion to murder Joffrey. “Would you do it?” Cersei asks, as Jaime remains silent. When accused of going to visit Tyrion in his cell, Jaime tries to convince Cersei that their brother is innocent, however, she refutes that he has always pitied Tyrion and firmly believes that he is the monster that killed their son. Cersei the commands Jaime that she wants four men at Tommen's door and abruptly dismisses him, referring to him only as "Lord Commander.” This illustrates the shift in their relationship that has now almost completely deteriorated over the events of the last few years from what it once was.

Some time later, Cersei is present at the coronation of her son Tommen as the new King of the Seven Kingdoms. Afterwards, Cersei approaches Margaery and tells her that she understands Joffrey was a monster, but as her first child, Cersei still loved him regardless. She also believes the newly crowned Tommen will make a good and decent king, but he needs guidance. Cersei asks Margaery if she is still interested in being queen, as Margaery responds in saying that she will need to speak to her father Mace about the matter.

Later, in the small council chambers, Tywin reveals to Cersei their problem with the Iron Bank of Braavos. They unfortunately owe “a tremendous sum,” and the gold mines of the Westerlands actually ran dry three years ago. Therefore, even though Tywin admits the Lannisters can trust nobody except themselves, they need the Tyrells' wealth and resources on their side. Cersei suggests coming to some arrangement with one of the Bank’s representatives, but Tywin dismisses the idea, since the Bank is a monolithic structure that cannot be avoided, cheated or swayed. Tywin insists they need the Tyrell’s investment in the crown more than ever, implying that Margaery is to remain Queen by now marrying Tommen. Tywin then informs Cersei that he cannot discuss Tyrion’s trial with her as one of the presiding judges. She coldly replies that she understands but then asks him to ponder what Tyrion deserves for lighting the Lannister legacy and future on fire.

Later that afternoon, in the gardens of King’s Landing, Prince Oberyn Martell is writing poetry on his parchment when Cersei requests a coversation. Oberyn admits that while he’s not a very good poet he learned from one his daughters adding that he has eight kin. Upon discussing his family, Oberyn mentions his deceased sister Elia Martell to which one his daughters was named after. Cersei ponders that even as he’s a legendary and feared fighter of high station he still couldn’t save his sister as she likens her own experience of losing her son. She pointedly asks the prince: “what good is power if you cannot protect the ones you love?” Oberyn replies in saying that “we can avenge them,” and then tries to ascertain whether Cersei truly believes her brother murdered Joffrey. As he mentions that through the trial they will learn the truth as Cersei responds by saying “we will have a trial anyway,” insinuating that truth isn’t necessarily the result of a trial. Cersei then asks Oberyn of a favor as she hasn't seen her daughter, Myrcella, in over a year. She asks him to have someone sail a new ship made for Myrcella down to Dorne since Cersei missed her last nameday, and to tell her that she loves her.

On the morning of Tyrion’s trial, a meeting of the small council is held, to which Prince Oberyn, who has now joined, rhetorically asks if their meetings will always be scheduled this early in the day. He then queries whether a title will be bestowed on him as he ponders the possibility as Master of Coin or Ships, to which the also-recently-added council member Mace Tyrell asserts that he is now Master of Ships. Lord Varys informs Tywin that Sandor Clegane has been spotted in the Riverlands. Cersei comments that he is a coward and now a traitor as Tywin orders a bounty on his head. Varys also informs the council of Daenerys Targaryen’s conquest of Meereen, who has now recruited a large army in addition to her three rapidly-growing dragons. Cersei asserts that one of Daenerys’ new advisors, Ser Barristan Selmy, was sent away from the Kingsguard as he wasn’t fit to protect Joffrey. Lord Tywin implies blame towards Cersei when he pointedly responds in saying that his grandson’s death wasn’t under Selmy’s watch. While Cersei insists that she isn’t worried about a “child” half-way across the world Varys reminds her of the Targaryen force Daenerys has built and Prince Oberyn also comments on the capabilities of the Unsullied army. Tywin decides to take measures to prevent her from launching an invasion.

That afternoon, Tyrion's trial begins with the newly-crowned King Tommen Baratheon recusing himself. Instead, a group of three judges are appointed to oversee the trial: Lord Tywin, Lord  Mace Tyrell and Prince Oberyn. Cersei has several witnesses testify against Tyrion, such as Ser Meryn Trant, Grand Maester Pycelle and Lord Varys. They all give strong, yet circumstantial, evidence of Tyrion's guilt. Cersei herself then takes the stand and quotes the threat Tyrion had informed her of regarding his planned revenge on her prior to the Battle of Blackwater. She also mentions Tyrion’s insistence of Joffrey fighting on the battlefield. After an hour's recess, Jaime comes to Tyrion and tells him that, when the verdict of guilty is pronounced, he must ask for mercy. Secretly, Jaime had made a deal with Tywin: in exchange for sparing Tyrion, Jaime will renounce his vows and return to Casterly Rock as Tywin's heir, while Tyrion will be sent to live out his days on the Wall with the Night's Watch. Tyrion points out that their father wanted this outcome all along. The plan is foiled, however, when Cersei calls on her last witness: Shae, Tyrion’s secret lover, who was assumed to have been sent away from King’s Landing around the time of Joffrey’s wedding. Her appearance astounds Tyrion as she testifies that he and Sansa Stark planned Joffrey's murder together, claiming that Sansa wanted vengeance for the murder of her family. She tells the judges of Tyrion's sexual desires, embarrassing him in front of the crowd. Tyrion, enraged beyond sense, demands that he be allowed to confess his crimes. He angrily roars about how he saved King's Landing from Stannis’ forces and urges that he should have let Stannis kill everyone instead. Tyrion then claims to be guilty, as Tywin assumes that he is guilty for murdering Joffrey. Tyrion denies this, asserting he is guilty of a "far more monstrous crime. I am guilty of being a dwarf!" Tywin scoffs at Tyrion's claims, informing that he is not on trial for being a dwarf. Tyrion angrily admits that he’s been on trial for his entire life as a dwarf. Tyrion then reveals his true feelings about Joffrey, denying guilt in the king's murder, however, admitting that he wished to have killed Joffrey himself. Tyrion then turns his full fury towards Cersei, informing her that watching her "vicious bastard" of a son die gave him more relief than "a thousand lying whores." He then turns around to the royal court and roars that he wishes to have become the monster they think he is and would have gladly give his life to watch everyone die from drinking poison. This enrages the entirety of the court as Tywin then orders Tyrion back to the dungeons beneath the Red Keep. Before he can be escorted out, however, Tyrion bellows that he will not lose his life for a crime he did not commit and, knowing that he will get no justice from the court, demands a trial by combat. 

A few days following the trial, Ser Gregor Clegane, known by most as "the Mountain,” is mercilessly killing prisoners with a greatsword. Cersei arrives and approaches the Mountain to thank him for his haste in returning to King's Landing as her champion for the trial by combat. Ser Gregor asks who he will be fighting, as Cersei then asks him if it matters. The Mountain simply shakes his head no.

Some time later, Tyrion is brought outside from his cell to witness the trial by combat that was demanded. Cersei remains reserved of her worry over the Mountain’s chosen opponent Prince Oberyn, a renowned fighter in his own right. The fight proceeds to be evenly-matched but Cersei’s growing concern of Clegane’s failure increases as Oberyn’s fast movement and skills begin to prove more effective than the Mountain’s brute force. Oberyn gains the upper hand and knocks the Mountain out cold but instead of striking for the kill Oberyn starts ranting about his sister’s death years ago at the hands of Clegane. However, this ultimately proves to be Oberyn's downfall, as Gregor comes to and manages to maneuver Oberyn to the ground and crushes his skull with his bare hands. Cersei watches proudly as the Mountain defeats him and smiles as their father sentences Tyrion to death.

Some time after the trial by combat, Cersei, Pycelle and Qyburn stand over Ser Gregor Clegane, who lies immobilized on a flat wooden table and is revealed to be suffering from a massive wound centered around his right side. Pycelle informs Cersei that the deceased Oberyn had coated his spear with manticore venom, poisoning Clegane. The effects are horrific, with Gregor's wounds putrefying and creating a terrible stench. Pycelle says that he is beyond any hope of recovery, but Qyburn insists to Cersei that he can save him using more unorthodox methods. Pycelle chafes at his suggestion, stating that he is not even a maester, and that such arrogance is what led to Qyburn's expulsion from the Citadel in the first place, for experiments that were deemed both dangerous and "unnatural." Cersei, determined to save Clegane from death, dismisses Pycelle and orders Qyburn to do whatever is necessary, infuriating Pycelle, who angrily shuffles out of the laboratory. She asks Qyburn if his treatment will work, and Qyburn claims that if his past work is any indicator, he stands a chance at saving Gregor. Qyburn states that the process will "change" him, although Cersei seems only concerned with whether it will weaken him, to which Qyburn assures that it won’t. Cersei departs as Qyburn begins siphoning out Gregor's tainted blood.

Afterwards, Cersei approaches Lord Tywin and insists that she will not submit to a forced marriage to Ser Loras Tyrell. He attempts to dismiss the subject by stating that the matter is closed, but she persists and says that it is not just because she does not love Loras: he wants to ship her off to Highgarden and remove her from the court entirely, keeping her away from her last remaining son. With Cersei out of the picture, both Margaery and Tywin will attempt to get their claws into Tommen, each trying to manipulate him into their allegiance. Tywin refuses to budge, so Cersei plays her trump card: she threatens to destroy House Lannister by telling everyone the truth. Tywin seems confused, and at first, Cersei scoffs that he is merely feigning ignorance. With growing realization, she assesses that even the brilliant Tywin Lannister never noticed what was going on between his own children, when all it would have taken was one attentive moment in the past twenty years. Tywin is still apparently confused, so with a merciless grin Cersei reveals that all of the rumors about her and Jaime as well as their children are true. Cersei then insists that she will tell everyone and destroy Tywin's vaunted family legacy, even though it will also mean her death and Tommen's death. Tywin shakes with barely constrained rage, but in denial, he accuses that Cersei is simply lying to anger him. Cersei asserts that she doubts he truly thinks that, then leaving him standing in his chamber alone.

Once she leaves Tywin’s chambers, Cersei then finds Jaime in the White Sword Tower. Still enraged over the trial and subsequent sentencing, Jaime expresses disgust at Cersei’s blatant attempts to have Tyrion killed. Cersei asserts that Tyrion killed their mother when she gave birth to him. Jaime is surprised that she still irrationally blames him for that, pointing out that he was an infant and had no control over what happened. He insists that Tyrion is her family, whether she chooses to accept it or not. Cersei rebukes his claim, insisting that Tyrion is not her family and that they all have a choice, and that she chooses Jaime. She then reveals that she has revealed their secret to their father. Jaime is stunned and concerned by her actions, asking how Tywin reacted to the news, but she states that she does not want to discuss their father. Cersei then begins to seduce him, saying she chooses her brother over everyone else in the world, no longer concerned with whether anyone else knows their secret. Jaime yields to her advances, kissing her passionately and throwing her on the table where they begin to have sex.