Several months later, Lord Tywin continues to lead his forces in defense of his grandson, King Joffrey, during the War of the Five Kings. He has suffered three significant defeats at the hands of newly-declared King in the North, Robb Stark, and his son Jaime still remains in the Stark’s captivity. Tywin’s regrouped forces are currently raiding the Riverlands from their base at the castle of Harrenhal. Most recently, Robb wins a further victory against Tywin's reinforcements during the Battle of Oxcross. Following Oxcross, Tywin returns to Harrenhal to find his courtyard full of prisoners and Ser Gregor Clegane and his men systematically torturing them to death. Lord Tywin orders an immediate halt to the tortures, saving a boy named Gendry at the last minute. He then rationally points out how disproportionate the torturing is, relative to what little wealth the peasants might be hiding. Tywin asserts that it would be far more efficient to put them to work around the castle, which is in great need of repair. It is noted that, as a blacksmith's apprentice, Gendry's skills are of particular use to them. Tywin then instantly notices that "Arry" is really a girl dressed up in boy's clothing, criticizing his soldiers for being too foolish to notice. What Tywin is unaware of, however, is that “Arry” is actually Arya Stark, Robb’s youngest sister who fled the capital after Lord Eddard’s execution. When Tywin asks her why she's dressed as a boy, Arya explains that it was safer to travel through the Riverlands under the guise. Tywin is impressed with her intelligence, and takes her on as his new cupbearer.

Days later, Tywin hosts a war council with five of his officers, as an incognito Arya serves them food, acting as Tywin’s cupbearer. Tywin rejects a suggestion stating that the Starks will struggle to sustain their army through winter, saying that the Northmen are more capable than they are of coping with cold. Ser Amory Lorch informs that their spies have reported growing discontent amongst the Northern Lords, who want to return home to gather the harvest. Tywin is dismissive, saying that they are at war and no-one is content. Tywin then informs that they have underestimated Robb Stark for too long, adding that their enemy has a good mind for warfare and is worshiped by his men. Arya brings a jug of wine to the table and Tywin halts her to ask where she is from, as she claims to have grown up in Maidenpool. He questions her about the lords there, testing her truthfulness. She is able to name House Mooton, but cannot recall their sigil. He says that she is a northerner and again asks her where she is from. This time she claims to be from Barrowton and correctly states their sigil. Satisfied, he then asks her for her view on Robb, as Arya states that the Stark king is known as the “young wolf” and is said to ride into battle on the back of a giant direwolf. She adds that they say that he cannot be killed. When Tywin asks what she believes, Arya asserts that anyone can be killed.

Some time later, Tywin hosts another war council in his chambers as Arya continues to serve as his cupbearer. Tywin orders her to fetch a book for him and realizes she can read. A Lannister captain then announces the arrival of Lord Petyr Baelish, who serves on the small council for Joffrey. Upon his arrival, Arya freezes in fear of recognition. Tywin asks for news from the capital and Baelish explains that he’s come from Renly Baratheon’s camp. Tywin jokes about the duration of Renly’s reign and repeats the rumor that he was murdered by a woman. Baelish says that there have been talk of other forces at work and Tywin dismissively insists that men love to blame demons when their grand plans fall apart. Petyr then offers to broker an alliance between House Lannister and House Tyrell. Tywin asserts that the Tyrell host has returned to Highgarden. Arya then spills wine on Petyr’s hand and apologizes as stares at her as he says that it was only wine. Tywin draws Petyr’s attention back to him when he asks if he would ride there himself, as they confirm that Baelish would leave that night. As Arya exits Tywin’s chambers, Lord Baelish begins to detail a meeting with her Arya’s mother, Catelyn Stark.

Later on, Lord Tywin looks down at the courtyard of Harrenhal from his balcony as a score of Lannister men have been hung and his officers continue to question their troops about the assassination of Amory Lorch. Tywin sniffs the dart that killed the knight and says that it was dipped in wolfsbane, a rare poison. He tells his subordinate Gregor Clegane that the killer was no common assassin. Gregor says that they have hung twenty men seeking the culprit and Tywin counters that he would not care if they had to hang a hundred. Tywin orders Gregor to attack the smallfolk of the region to show them what it means to choose the wrong side. Gregor leaves to carry out his orders as Arya serves a meal to Tywin. Tywin questions where Arya learned about history and she claims that she was taught by her father. Tywin is dubious about the idea of a well read stonemason, saying that he has never met one. Arya asks if he has met many stonemasons and he warns her to be careful with her tone, saying that he enjoys her but has limits. He orders her to return the meal to the kitchen to finish it there. He criticizes her pronunciation of “my Lord,” warning her that lowborn girls say “milord.” He says that if she is going to pose as a commoner she should do it properly and she claims that she was taught to speak properly by her mother, a maid to Lady Dustin. Tywin says that she is too smart for her own good and dismisses her.

Some days later, Arya serves drinks whilst Lord Tywin hosts another war council. His brother Kevan Lannister predicts that King's Landing will fall an hour after the rivaling king Stannis Baratheon’s forces arrive. Kevan counsels Tywin to order his daughter Cersei Lannister and her children, including King Joffrey, to flee to the safety of their ancestral home of Casterly Rock. Tywin balks at surrendering the Iron Throne, believing that a king who runs cannot remain king for long, adding that Joffrey must stand and fight. Tywin then steers the council back to Robb Stark, who is on their doorstep in the Westerlands, blaming their lack of intelligence on his son Ser Jaime’s capture. Tywin then admits that Robb is a boy who has never lost a battle and will take risks because he does not know enough to be afraid. He announces his orders; the army will ride out from Harrenhal that evening to get a night’s march before Robb is aware that they are coming. He names Ser Gregor as his castellan at Harrenhal and orders him to continue his efforts against the Brotherhood Without Banners, a group of outlaws working against the interests of House Lannister throughout the Riverlands who act as protectors of the smallfolk. Tywin then assigns Arya to serve Ser Gregor, stating that she has been a good servant.

Some time later, during the Battle of the Blackwater, Tyrion leads the Lannister army through the tunnels beneath the city and is eventually able to defeat Stannis' troops manning a battering ram. On the battlefield, Tyrion fights off a handful of Baratheon men but amidst the chaos he is suddenly attacked and betrayed by Ser Mandon Moore of the Kingsguard. Mandon attacks Tyrion with the intent of killing him but misjudged the distance and only slashes Tyrion across the face with his sword. Before he can strike Tyrion again, Tyrion's squire, Podrick Payne, kills Ser Mandon from behind with his spear. Tyrion, barely conscious and held by Podrick, watches a seemingly lost battle before losing consciousness. Meanwhile, Cersei Lannister brings her young son, Tommen Baratheon, to the throne room and sits with him on the throne, distracting him with a story about a young lion, and readying a vial of poison for them both to drink in the event of a lost battle. Just in time, however, the combined forces of Tywin and his new allies of House Tyrell join the battle and decimate Stannis’ army. The survivors flee to their ships as Stannis is dragged away from battle by his guards. Tywin and Ser Loras Tyrell  burst into the throne room to announce their victory, just in time to stop Cersei from killing herself alongside her son. Tywin triumphantly informs his daughter that the battle is over and they have won.

Following the battle, Tyrion's important role in defending the city is not acknowledged and he is left to recover from his wounds. With Tywin’s return, his son is stripped of his power and title as Hand of the King. Rumors also circulate that Cersei is the one who ordered an attack on her brother at the hands of a Ser Mandon Moore. Meanwhile, a public ceremony is held in order to reward those who aided the city in the victorious battle. Lord Tywin is officially recognized as the new Hand of the King, as well as being named the ‘Savior of the City,’ while Lord Baelish is awarded Harrenhal for brokering the alliance between House Lannister and House Tyrell. Ser Loras Tyrell is then offered a favor of his choosing, as he asks King Joffrey to marry his sister,  Lady Margaery Tyrell, who was prevously betrothed to Renly Baratheon. Joffrey states that he cannot, as he is constrained by his betrothal to Lord Eddard’s eldest daughter, Sansa Stark. Cersei, however, 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. A relieved Sansa Stark, a captive of the Lannisters for several months, is relieved by this news. Lord Baelish informs her, however, that this won’t stop Joffrey from tormenting her

Some time later, Lord Tywin is writing a letter in his chamber as Tyrion enquires how he is finding the job as Hand. Tywin is not amused, however, asserting that instead of acting as Hand, Tyrion instead spent his days sleeping with whores and drinking with thieves. An angry Tyrion informs his father that he wants to receive some gratitude for leading the defense of the city but Tywin is unmoved, saying that Lannisters do not require applause and points out he has seven kingdoms to run. Tyrion insists that he is the rightful heir to Casterly Rock, the ancestral stronghold of House Lannister, and wants Tywin to acknowledge that. Tywin, stoic, agrees that Tyrion needs better quarters and will also be given a position of authority. Then Tywin angrily informs that he will be consumed by maggots before he makes Tyrion heir to Casterly Rock, adding that he is an ill-made and spiteful little creature full of lust and low cunning who killed his mother, Joanna Lannister, to come into this world. Tywin cannot prove that Tyrion is not his, so he must let him wear the family's crest, but will be compelled to let Tyrion turn Casterly Rock into his whorehouse. He then dismisses Tyrion and threatens the life of the next whore he finds in his son's bed, highlighting Tyrion’s traumatic past with a whore years ago.

Some weeks later, as Tywin is fishing out into Blackwater Bay, he is approached by Grand Maester Pycelle, who apologies for his interruption. He requests to speak with Tywin over a few matters ahead of the small council taking place later that day. Tywin is quick to state that Pycelle is no longer on the council, as the Grand Maester admits that Tyrion did conspire in keeping him from the council when acting as Hand. When Tywin asserts that he himself hasn’t revoked his son’s decree, Pycelle begins to stammer in disbelief, ttrying to find his words. Tywin then interrupts Pycelle and tells him to drop the feeble, elderly routine that he’s been putting on for years. Tywin asks the maester if he’s the only one to see through his performance. Pycelle suddenly stands up perfectly straight and begins to speak normally without an affected voice, further displaying a lack of infirmity. Pycelle admits that he is surprised himself to have fooled so many people for so long, explaining that he prefers to be seen as weak so to survive the duplicity of the high lords. When Tywin then asks why he should be invited back into the council, Pycelle reminds him that he has unfailingly served House Lannister ever since arranging Tywin as Hand during the Mad King’s reign. Allowing him to return to the council, Tywin then states that Pycelle will serve him more actively, as befits a man with such “vigor.”

Afterwards, Lord Tywin calls the first meeting of the small council since he arrived in the city and assumed his position as Hand to his grandson Joffrey. He has the meeting place changed to a room next to his own quarters in the Tower of the Hand, asserting his dominance. All of the seats are on one side of the table, as a non-verbal test to see how each of them react. Petyr Baelish ambitiously pushes his chair past everyone else to be the one who sits closest to Tywin. Lord Varys rolls his eyes at Petyr’s naked ambition and lets him pass. Cersei pulls up a chair so she is sitting at Tywin's right hand and Tyrion himself takes a new chair and makes a point of dragging it across the ground until it is positioned at the opposite end of the table from his father. Tywin is upset with his three advisors, also including Pycelle, as none of them can locate his son Jaime, even though the entire Northern army has heard of his escape from the Stark camp. Varys makes a jab at Baelish's titular promotion with Harrenhal and impending betrothal to Lysa Arryn, as Tywin states that this will cement support from the Vale , which has been neutral in the war up to now. Tyrion then points out that if Baelish departs for the Vale that leaves a vacancy on the small council, and Tywin reveals that he has appointed Tyrion as the new Master of Coin. Tyrion quickly points out that he has no prior experience in finance. With backhanded compliments, Cersei makes it clear that this promotion is really intended to give her brother an opportunity to make mistakes he will later be blamed for.

Some time later, Cersei meets with her father Tywin in his chambers as she wants to ensure that he is doing everything he can to find his son Jaime. 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. She claims she is the only one of his children who ever took his lectures on legacy seriously. Cersei then points out that for a man who pays a lot of lip service to "family" and "legacy," he excludes her from his plans. Tywin admits that he excludes Cersei from his plans 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 House Tyrell at court, and something must be done about them. In particular, Cersei is nervous about how skilled Margaery Tyrell is at manipulating the young king. Tywin bluntly responds that it's a good thing someone has finally been able to manipulate Joffrey, as Cersei herself has been incapable. She retorts that Tywin should try stopping Joffrey from doing what he likes, implying he will find it extremely difficult, but her father firmly responds, "I will."

Later on, Tywin summons Tyrion to the Tower of the Hand in order to explain that the Tyrells are plotting to wed Sansa Stark to Loras Tyrell. He states that he will not allow them to steal "the key to the North" out from under him. Tywin explains that King Robb’s days are numbered and Theon Greyjoy murdered Robb's younger brothers, Bran and Rickon Stark, which makes Sansa the heir to the North. Tywin then insists that he has no intention of letting the Tyrells get the upper-hand on this arrangement. He also notes that the Tyrells won't go through with their plan until after Joffrey's wedding, which means they need to act first, by finding Sansa another husband. When Tyrion realizes his father is implying that he will marry Sansa, Tyrion protests but Tywin asserts that Sansa is a far better reward for Tyrion’s efforts at the Battle of the Blackwater than he could ever expect. Cersei gloats over the matter, but her smug attitude quickly evaporates when her father commands that she will wed Ser Loras instead of Sansa. Cersei flatly refuses, but Tywin is insistent: the marriages of Cersei and Tyrion will place the North and the Reach firmly in the Lannisters' control. He adds that her marriage to Ser Loras will also put an end to what Tywin calls "the disgusting rumors" being spread about her and Jaime’s incestuous relationship, as well as the parentage of Cersei’s children. Tywin refuses to listen to either of his children’s protests and storms out in disgust, raging that the pair have disgraced the Lannister name for far too long.

Some time later, Lord Tywin meets with Lady Olenna Tyrell to discuss having her grandson Ser Loras marry his daughter Cersei. They trade barbs when Olenna brings up Cersei's age and her capability to have more children. Tywin himself then cites the rumors of Loras' well-known homosexuality, to which Olenna matter-of-factly confirms when stating Loras is “a sword-swallower through and through.” Tywin is adamant that the two wed but Olenna blatantly refuses to consent, stating her grandson is the most desirable bachelor in Westeros. She then hints at King Joffrey being the result of incest between Cersei and her brother Jaime, making him claim to the throne illegitimate. Tywin replies that if that is true, Joffrey has no right to the throne and the Tyrells just "threw a flower into the dirt," implying Margaery’s arranged marriage to his grandson. Olenna says she will not risk "throwing another flower into the dirt" if Cersei cannot bear heirs for House Tyrell. Realizing her unchanged position on the matter, Tywin threatens to make Ser Loras a knight of the Kingsguard, which would force Loras to give up his right to marriage and to inherit his home of Highgarden. With her hands tied, Olenna eventually relents and consents to the marriage of Loras and Cersei.

Days later, Tywin enters the throne room to answer a summons from King Joffrey, who requests an update on what the small council has been doing. Tywin informs Joffrey that the king can always attend the meeting should he desire it, which turns into a conversational power play between the two. Joffrey then changes the subject to Daenerys Targaryen, a dragon queen from the eastern continent of Essos who is preparing an invasion on the Seven Kingdoms, as her ancestors once had. Tywin is surprised that Joffrey even knows about the exiled princess. Tywin admits the reports are true that the last Targaryen is not only alive, but has hatched the first dragons the world has seen in almost two centuries. Tywin reminds Joffrey that the last dragons were stunted creatures who weren't grand weapons of war. Moreover, Tywin says that even if Daenerys' dragons do turn out to be as strong as the dragons of centuries long ago, they are on the far side of the world and no threat to Joffrey's rule. Tywin also warns his grandson that he should heed his advisor's council on matters he does not comprehend. When Joffrey protests that he hasn't been counseled on anything, Tywin says he is being advised at this very moment and says that he will inform Joffrey should he deem it necessary. Their exchange leaves no doubt as to who is really ruling the kingdom.

Some time later, Tyrion speaks with Sansa before their wedding, though he knows the Stark girl is not thrilled at the prospect of marrying him. Tyrion promises Sansa that he will not mistreat her, and Sansa agrees there are worse Lannisters she could be wed to. Later, inside the Great Sept of Baelor, Margaery Tyrell tries to ingratiate herself to Cersei, commenting that they will technically be sisters soon. Cersei responds by telling Margaery the story behind the song "Rains of Castamere," relating how it refers to the destruction of House Reyne after their failed rebellion against House Lannister. This implies the 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; King 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 as the High Septon then 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 Tywin’s insistence that his inebriated state will render him unfit to impregnate his wife. At the same time, King Joffrey himself is drinking too much wine and his behavior becomes increasingly offensive to both Sansa and Tyrion. Against Cersei's ineffectual protests, Joffrey gets up and 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. Cersei then retreats to an upper gallery and brushes off a conversation with Ser Loras. 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. Tywin assures the court that Tyrion is heavily drunk and after tensions subside, Tyrion and Sansa leave the feast.

Weeks later, Tywin and the small council receive a message from Lord Walder Frey informing that Robb and Catelyn Stark are both dead. Joffrey gleefully states that he intends to serve Robb's severed head to Sansa at his wedding as a deeply embarrassed Cersei insists that Joffrey was only joking. Tyrion tells Joffrey that Sansa isn't his to torment anymore as Joffrey angrily proclaims that he is the king, and everyone is his to torment. Tywin counters that any man who has to remind his subjects that he is king, is no true king. Joffrey then attempts to fight his grandfather, deriding Tywin as a coward who hid while Joffrey's "father" King Robert won the real war that overthrew the Targaryens. Tywin calmly declares that the king is tired and advises Cersei to see him to bed. Tywin then dismisses the council, save Tyrion, who confronts Tywin about his part in the Red Wedding, showing distaste for the choice of a wedding as a place to inflict the slaughter of House Stark. Tywin then asks Tyrion why killing ten thousand soldiers in battle is nobler than killing a dozen guests at a wedding. Tywin then states that Roose Bolton is Warden of the North until he impregnates Sansa, but Tyrion assures him that he won't do it, demanding to know when Tywin ever put the family's interests above his own. Tywin brutally admits that that he did exactly that on the day Tyrion was born, wanting to throw his dwarf newborn into the sea, but instead he spared him because he is a Lannister.

With his family victorious over the Starks, Lord Tywin has the Stark ancestral greatsword melted down and reforged into two smaller longswords, while he personally burns down the wolf pelt scabbard of Eddard Stark's sword. Afterwards, the newly-returned Jaime Lannister is offered a sword by his father, which is made of Valyrian steel from Stark sword. Jaime comments that House Lannister has always wanted its own Valyrian blade and Tywin answers that they now have two. The original was absurdly large and had plenty of steel for two swords. Jaime returns to the capital, however, missing a hand due to a grisly altercation in the Riverlands during his journey back. Tywin then reveals to Jaime his plan to have him removed from the Kingsguard, a job he is now deemed incapable of holding, so that he can return to Casterly Rock and rule as Lord in Tywin’s stead. However, Jaime tells him that he has no plans of resigning and that he will remain in King's Landing to protect King Joffrey, as well as secretly continue his incestuous relationship with Cersei. Jaime also rejects that this is about his honor, as he believes that his honor is too far gone, so he might as well do what he wants rather than what is expected of him. Tywin agrees to let him do so, but tells him that he no longer considers him a Lannister. Despite this, Tywin allows Jaime to keep the sword, saying that a “0ne-armed man with no family needs all the help he can get”.

On the morning of King Joffrey and Lady Margaery’s wedding, a breakfast is held. Lord 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 Stark’s handmaiden and informs Lord Tywin that she is Tyrion's whore. Realizing Shae must be the whore Tyrion brought to court with him, Tywin 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 Podrick Payne, Tyrion's squire, presents Joffrey 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”. Afterwards, in order to save her life from an attack made on behalf of Tywin, Tyrion informs the brokenhearted Shae that there is a ship waiting for her bound for Pentos and that their "friendship" is at an end.

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. At the wedding feast, Lord Tywin is confronted by Olenna Tyrell about the growing economic problems the Iron Throne is facing, especially with the Iron Bank of Braavos growing restless over their inability to repay the debt. Afterwards, Tywin and Cersei then meet Prince Oberyn Martell and Ellaria Sand, who are visiting from Dorne. The conversation is filled with veiled threats between Oberyn and Tywin, and he reminds him that his granddaughter, Myrcella Baratheon, is in Dorne, possibly hinting that he is planning to use her as a hostage against the Lannisters. The four get into a heated discussion when Cersei hypocritically mocks Ellaria's bastard-born 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 and Tywin’s embarrassment. 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 fool, 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, Lord 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, a grieving Cersei and her youngest son, Tommen Baratheon, privately pay their respects to Joffrey in the Great Sept of Baelor. Lord Tywin wastes no time and begins instructing the young prince on the qualities of a good king. Tommen knows that he will become king but doesn't know what kind of ruler he will be. After commenting on his belief that Joffrey was neither a wise nor good king, Tywin adds that if he had been either perhaps he would still be alive. Tywin tells Tommen that a wise king listens to his advisors, even after he is old enough to have some wisdom himself. As Tywin and Tommen leave, Ser Jaime enters to see his sister, who is calling for the death of their accused brother Tyrion and his missing wife Sansa. Jaime sends the septon and septas away so he can be alone with Cersei. He tries to comfort her through his affections as she reciprocates, initially, then pulls back from him. An also grieving Jaime tells her she is a hateful woman and rhetorically asks “why have the gods made me love a hateful woman?” whilst grabbing her forcefully. He becomes more aggressive with his advances, trying to latch onto some form of comfort with Cersei. She is drawn to his advances to a degree, however, it’s a highly inappropriate place for sex. Her body reacts with such respect and then asks Jaime to stop by repeating "it isn't right.” With increased aggression, however, Jaime refuses to stop, and tells her "I don't care." They then proceed to have sex next to Joffrey’s dead body.

Afterwards, Lord Tywin interrupts Prince Oberyn Martell with Ellaria Sand to discuss Tyrion's upcoming trial for the murder of King Joffrey. Once in private, Tywin brings up Oberyn's knowledge of poisons and the link between that and Joffrey's death, wondering whether Oberyn had helped Tyrion. The topic quickly changes to the murder of Oberyn's sister Elia Martell by Tywin's "pet", Ser Gregor Clegane, during the Sack of King's Landing. Tywin denies ordering her death, but promises to arrange a meeting between Oberyn and the Mountain so he can hve his justice. He also offers Oberyn a position on the small council, if he agrees to be the third judge at Tyrion's trial. Tywin explains that he is eager to bring Dorne back into the fold, wanting to unite the kingdoms against more obvious threats; the Greyjoys are in open rebellion, a wildling army is advancing on the Wall, and Daenerys Targaryen is in Essos with three dragons and building a powerful army. Tywin observes that only the Dornish successfully resisted Aegon Targaryen's dragons during his invasion of Westeros three centuries ago. Oberyn dryly notes it must be hard for Tywin to admit he needs the Dornish for help. Tywin admits that they need each other, who adds that he will help serve justice for Elia’s murder.

Days later, Tommen Baratheon is crowned king of the Seven Kingdoms on the podium in front of the Iron Throne to enthusiastic applause. Afterwards, Tywin reveals to his daughter Cersei their problem with the Iron Bank of Braavos, as Lady Olenna had previously warned him. They unfortunately owe “a tremendous amount”, 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, he is insistent that 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. When the topic of Tyrion’s imprisonment circles around, Tywin informs that while as a mother Cersei has every right to discuss the matter, however, as he will be one of the presiding judges he cannot discuss the impending murder trial with her. She informs her father that she respects that and there is no need to discuss it. However, before leaving, she then coldly replies to Tywin and asks him to ponder what her brother Tyrion deserves for lighting the Lannister legacy and their future on fire, still insistent that he is the culprit who poisoned Joffrey.

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, the brother of Ser Gregor, has been spotted in the Riverlands after leaving the capital during the Battle of the Blackwater. Cersei comments that the former bodyguard to King Joffrey 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.

Some hours later, in the dungeons of the Red Keep, Ser Jaime Lannister enters Tyrion's cell to escort him to his trial. Tyrion immediately jokes about being pardoned but Jaime’s solemn face dashes any momentary attempt at humor. As he is brought to the throne room in chains, Tyrion’s trial begins with the newly-crowned King Tommen recusing himself. Instead, a group of three judges are appointed to oversee the trial: Lord Tywin, Lord Mace Tyrell of the Reach and Prince Oberyn. With the trial quickly underway, Cersei Lannister has organized several witnesses to testify against Tyrion on the stand, such as Ser Meryn Trant and Grand Maester Pycelle, who exhibits the poisoned necklace Dontos Hollard gave to Sansa Stark, which at some point had been found when Dontos’ body was recovered in Blackwater Bay. Then to Tyrion’s surprise, Lord Varys testifies against him. Everyone provides strong, yet circumstantial, evidence of Tyrion's guilt. Tyrion seems particularly hurt by Varys' betrayal, so much that he asks the spymaster in front of the court whether he remembered what he had told Tyrion about his heroic efforts after the Battle of the Blackwater. Varys solemnly tells Tyrion that he never forgets anything.

During recess, Ser Jaime speaks privately with his father Tywin in his chambers and asks to spare Tyrion, offering to break his oath to the Kingsguard and return to Casterly Rock as Tywin’s heir. Tywin quickly accepts the arrangement and informs Jaime that Tyrion will be allowed to join the Night's Watch after being found guilty of Joffrey Baratheon's murder, provided he pleads for mercy. Before the recess ends, Jaime speaks with Tyrion and urges him to plead guilty. Tyrion is deeply distrustful of the offer, remarking that Eddard Stark was promised the same thing and yet still lost his head, but Jaime pleads with his brother to trust him, insisting that their father will keep his word, and advises him to "Keep your mouth shut. No more outbursts."

Returning to the trial, Tywin then orders a surprise witness to the stand: Shae. Her appearance astounds Tyrion, who had assumed she had been safely sailed to Pentos. Shae testifies that Tyrion and Sansa planned Joffrey’s murder together, claiming that Sansa wanted vengeance for the murder of her family. She also tells the judges of Tyrion's sexual desires, embarrassing him in front of the crowd. When Tyrion pleads for her to stop she turns to look at him and bitterly says “I am a whore, remember?” Before she can continue however, Tyrion, enraged beyond sense, angrily demands that he be allowed to confess his crimes. He angrily roars about how he saved King's Landing but should have let Stannis Baratheon kill everyone in the capital, much to the horror and disgust of the people in the court. Tyrion then claims to be guilty. Tywin formally asks for him to admit to the court of the murder, however, Tyrion denies this, saying he is guilty of a "far more monstrous crime. I am guilty of being a dwarf!" Tywin scoffs at Tyrion's claims and says he is not on trial for being a dwarf. Tyrion angrily says he has been on trial for that his entire life. Tywin asks if he has nothing to say in his defense. Tyrion then says he has nothing to say in his defense, however, reveals his true feelings about Joffrey, denying the murder but saying he wished to have killed Joffrey himself. Tyrion then turns his fury towards Cersei and says that watching her "vicious bastard" die gave him more relief than "a thousand lying whores". He then roars to the court that he wishes to be the monster they think he is and would gladly give his life to watch everyone die from drinking poison. This enrages everyone in the court as Tywin then orders Ser Meryn to escort Tyrion back to the dungeons. Before he can be escorted out, 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. Feeling there is nothing left to lose, Tyrion then locks eyes with his father and cracks a subtle smirk after his demand that has astonished the court and Tywin himself.

Some time later, the shackled Tyrion is brought to the arena, where a large crowd has assembled for the trial by combat. Tyrion grows apprehensive to find a helm-less Oberyn drinking, and wearing very light armor – in comparison to his opponent, Ser Gregor, who is clad from head to foot in heavy armor. Oberyn dismisses Tyrion's concerns, noting that he always drinks before a fight and favors speed over protection. As Gregor and his squire make their way to the arena, Pycelle begins a speech asking the gods to favor the innocent before Tywin cuts him short and begins the trial by combat. Oberyn, after impressing the crowd with a display of acrobatic spear maneuvers, goes on the attack, stabbing out at Gregor and moving out of the knight's reach, forcing Gregor to tire himself out chasing his opponent. As he evades Gregor, Oberyn repeatedly taunts Gregor by constantly bringing up his part in the murder of his sister, Elia Martell, and her children, and demanding a confession. Oberyn pins Ser Gregor to the ground with his spear, but his hopes are quickly shattered in the moment when the Mountain knocks Oberyn down and crushes his head in, sealing Tyrion's fate. As Tyrion is struck with horror, Lord Tywin states that the gods have made their will known and his son is sentenced to death.

Some weeks later, 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.

In the middle of the night, Tyrion is awoken in his cell as his brother Jaime has orchestrated an escape plan for Tyrion with the assistance of Lord Varys, who has secured a galley in the harbor so he can flee to the Free Cities. Before the siblings part ways, Tyrion and Jaime embrace and bid each other farewell, unsure if either will ever see each other again. Before Tyrion escapes, however, he decides to infiltrate his father's chambers, only to find a woman lying in Tywin's bed. As he draws closer he sees that the woman is Shae, who thinks it is Tywin and calls out for him, calling him "my lion" as she had once done to Tyrion. When she turns over and sees that it is Tyrion, looking utterly betrayed, she grabs a knife to defend herself. Tyrion then rushes forward onto the bed to wrestle the knife from her grasp. Tyrion eventually manages to knock the knife from her hands and grabs the necklace around her throat and starts to strangle her with it in a fit of rage. Tyrion continues to strangle her long after she has stopped resisting as he then sinks to the floor and sits next to Shae's lifeless body, weeping, and tells her that he's sorry. He stares at the wall across the room and sees the late Joffrey Baratheon's old crossbow, and his expression quickly darkens.

Tyrion takes the crossbow and heads down the hall to the privy, to find his father seated upon the toilet. Tywin seems surprised to see Tyrion, but quickly regains composure and asks Tyrion to lower the weapon while attempting to defuse the situation. Tywin insists that he was never going to have Tyrion killed. Tyrion then admits that he just murdered Shae, but Tywin scoffs that it doesn't matter as she was nothing more than a whore. Tyrion threatens that if his father says the word "whore" one more time he will kill him. Tywin balks that Tyrion won't kill his own father in the privy, however, the moment Tywin utters the word "whore" again, Tyrion loosens his crossbow bolt, hitting Tywin in the belly. Tywin is incredulous that Tyrion actually had the courage to fight back against him. As Tyrion reloads the crossbow, Tywin angrily declares that Tyrion is no son of his. "I am your son", Tyrion replies quietly, "I have always been your son", and fires a second bolt into Tywin's heart, killing him. Tyrion discards the crossbow and leaves to find Varys, who immediately realizes that Tyrion has done something terrible. Nonetheless, he leads Tyrion out of the castle to the docks where Tyrion is stowed away inconspicuously in a crate aboard the ship. Varys notices the bells begin to toll, signaling the discovery of Tywin's body, and heads back for the ship, sitting next to Tyrion's crate in silence as they both cast off into the Narrow Sea towards Essos. 

Some time later, escorted by Ser Meryn Trant of the Kingsguard, Cersei walks to the Great Sept of Baelor for her father Lord Tywin's funeral, surrounded by numerous lords and ladies, including Margaery Tyrell, who she glances at suspiciously. Cersei is stopped by the High Septon, who suggests to her that they start soon, since lords and ladies have come from all over Westeros, but she says they will wait a little longer while she has a moment alone with Jaime and their father's corpse. Inside, over their father’s body, Cersei notes that Tywin never wanted him to be Kingsguard yet here Jaime is protecting his body. Jaime warns that all the power and prestige Tywin built for House Lannister belongs to them now, and that once everyone sees that Tywin is truly dead, their enemies will do everything they can to take it away from them. Cersei bluntly states that the person who “tore us apart” and their true enemy is their brother Tyrion. She then adds that Jaime is partly responsible for Tywin's death since he was the one who released their father's murderer. Cersei coldly declares that “Tyrion may be a monster, but at least he killed our father on purpose. You killed him by mistake, with stupidity.”

*In the aftermath of Tywin’s death, follow Jaime, Cersei or Tyrion's journey throughout the rest of the series.