Locked in a barred cell on the back of a wagon, Jaqen H'ghar is in imprisonment when his party is being led north by a Night’s Watch recruiter named Yoren, who recently departed from King's Landing, the capital city of Westeros. Traveling towards the Wall alongside Jaqen and his cellmates, Rorge and Biter, are fellow recruits Gendry, Hot Pie, Lommy, and a girl named Arya, who has been smuggled out of the capital and is disguising herself as boy named “Arry”. When the party stops in the Riverlands, Jaqen calls over "Arry" and asks her to fill a tankard with water and tells her that he has not drunk for a day and a night. In the culturally-humbling Lorathi dialect, Jaqen always refers to himself as “a man” and Arya as “a boy”. The prisoner Rorge rattles the cage and threatens Arya, as Jaqen then asks Arya for forgiveness and insists to her that he has not chosen his companions. He introduces himself and states that he is from Lorath. Rorge then demands beer and insults Arya. She curtly states that he should have asked nicely, drops all but one of her sticks and uses it to hit Rorge’s hand. He recoils and then tries to grab her through the cage. Meanwhile, the third prisoner named Biter moves up behind Rorge and hisses at Arya, who is threatened again Rorge. Jaqen smiles at Arya and informs her that she has more courage than sense, as she backs away and leaves the bound trio.

Some days later, Jaqen is stopped overnight when the party are interrupted by horns sounding outside. As the recruits rush outside, one man trips and drops his torch, setting a fire near the prisoner wagon. Yoren and the recruits are met by Ser Amory Lorch and a force of men loyal to House Lannister. Lorch points out the Gold Cloaks with him, asserting that they have come for Gendry. Lorch then orders Yoren and the recruits to drop their weapons, but Yoren remains defiant, killing several men before he is overwhelmed. Lorch himself kills Yoren by driving his sword through the back of his neck. Seeing their leader killed, Gendry and many of the other recruits join the fight. Arya is distracted by Jaqen calling for help, as the flames start enveloping the cage. She hands him an axe before rushing to join the fray. Jaqen does not fight against the Lannister men, though he's surprised that Arya helped him. Amory Lorch orders the survivors to be rounded up and taken to Harrenhal. With a crossbow arrow in his leg, Lommy calls for help from the ground. A man named Polliver approaches and slowly stabs him through the throat. As Polliver walks away from a dying Lommy, Lorch demands that the survivors identify Gendry. Arya witnesses a worried Gendry and the other recruits as she then announces that they’ve already killed Gendry, pointing out the bull helm lying next to Lommy’s body.

Some weeks later, when Arya reaches the water butt in the ruins of Harrenhal, she finds a Lannister helmet left atop it. Jaqen suddenly approaches her, who is now dressed in Lannister armor, as he cautions her to keep his identity as prisoner a secret. Jaqen comments on Arya “becoming a girl,” stating that he was always aware, but that it was not his place to spoil her secret. Jaqen then informs that a man pays his debts and that he owes her three. Arya misunderstands him and he explains that “only death can pay for life” and as Arya saved him during the fire, Jaqen means to repay her by taking three lives on her behalf. She is intrigued at the idea of being able to choose anyone and asks Jaqen to kill the Tickler, Ser Gregor Clegane's interrogator who has been picking off prisoners one by one. Later on, Arya watches Gendry tempering a newly forged blade in the smithy. She criticizes his stance, telling him he should be stood side face and adding that if he is practicing for a fight he should do it properly. A woman then screams in the adjacent courtyard and they rush to see what has happened. They find the body of the Tickler surrounded by Lannister men-at-arms. Hot Pie is among the stunned onlookers as Arya looks up at the ramparts and sees Jaqen casually eating an apple. He puts a single finger to his face, indicating his first kill on her behalf. She then cracks a justified smile.

Later on, in Lord Tywin Lannister’s chambers, his new cupbearer Arya looks at a letter sitting on his desk. It concerns troop movements and reports ten thousand men heading for the Golden Tooth stronghold in the Westerlands, while her brother Robb Stark, the King in the North, is moving south along the coast. Tywin catches her and asks who taught her to read, who informs that it was her father. When pressed, Arya claims that her father was a stonemason who taught himself to read and that he was killed by loyalty, only the latter part being the truth, as her father was the Hand of the King to Robert Baratheon prior to both of their murders that were orchestrated by the Lannisters. Arya then steals the letter while Tywin distracts himself when reminiscing about his own father, Tytos. Arya reads the letter outside and then bumps into Ser Amory Lorch, who takes the letter from her, asking why she has it. She claims that she was asked to deliver it to the armoury. Amory looks at the letter and wonders why Tywin would do that. Arya then flees across the courtyard as he gives chase. She hides from him and he turns back towards Tywin’s chambers. Arya then searches for Jaqen H’ghar and urgently names Amory as her second kill. Jaqen accepts her instruction but she insists that he must be killed immediately. Jaqen informs that he will act when the time is right, but eventually relents to Arya’s urgency. Ser Amory opens the door to Tywin’s chamber and then collapses forward with a dart in his neck.

Some weeks later, after realizing that she has missed her chance to kill Lord Tywin by giving Jaqen his name as the third kill, Arya comes upon the assassin, who asks her to name someone else instead. She leans forwards and whispers his own name in his ear. Jaqen angrily warns her not to mock the gods, however, she insists that she is serious. He firmly asks her to un-name him and she eventually agrees to do so, only if Jaqen helps her escape from Harrenhal. He predicts that it would require more than one life and exceed the terms of their agreement. Arya names him again as he then accuses her of being dishonorable. She shrugs, unconcerned. Jaqen stands up, informing her that if he helps she must obey him. He tells her to walk through the gate at midnight with her friends. Late that evening, Arya, Hot Pie and Gendry gather in the shadows opposite the gate. Gendry asks Arya what Jaqen told her to do about the guards, who admits that he only instructed her to walk through the gates at midnight. Gendry warns against trusting the man who fled when she freed him from captivity. However, Arya stands and bravely walks toward the gate. Gendry and Hot Pie hesitantly follow her and, as they approach the gate, they realize that Jaqen has killed all of the Lannister guards in the courtyard. They’ve also been pinned in place so as not to raise the alarm. The trio passes through without being noticed.

Days later on, Arya, Gendry and Hot Pie trek through the Riverlands, they are surprised to see Jaqen waiting for them on a stone outcrop. Arya asks why he is there and he informs that he was waiting for her. Arya then asks him instead how he killed the guards and if it was difficult. Jaqen asserts that it was no harder than taking a new name if you know how. He then offers to take Arya to the Free City of Braavos in order to train with the Faceless Men assassins, adding that he knows the list of names that she whispers, suggesting they could all be offered to the Lord of Light. Arya declares her interest in going but informs Jaqen that she can’t, as she needs to find her family. Jaqen then hands her an iron coin, explaining that it’s a coin of great value. He instructs that if Arya decides to follow him at any point she should give the coin to anyone from Braavos and say to them “Valar Morghulis.” Arya repeats the phrase as Jaqen walks away. She then pleads with him not to go but he informs her that Jaqen is dead, asking her to repeat the phrase again and complimenting her on her pronunciation. He turns away and bows his head. When Jaqen turns back to her, his face has changed entirely to another man. He bids her farewell in a new voice as Arya looks down at the coin and then back at Jaqen walking away.

Several years later, following the Red Wedding massacre which resulted in the deaths of her brother King Robb, as well as her mother Catelyn Stark, Arya uses the Braavosi coin that was given to her by Jaqen H’ghar and sails across the Narrow Sea to Braavos. After a long sea voyage, she arrives in the Free City with the ship captain Ternesio Terys. Arya is awestruck by the giant statue of the Titan of Braavos, which, according to the captain, would wake and protect the city whenever Braavos stood in danger in the old times. Upon her arrival to the Faceless Men’s headquarters, the House of Black and White, Arya calls to the door of the ancient building. The door opens by a hooded man as Arya pulls out her coin stating that Jaqen had given her this and was sent here by him. The elder taciturn man rejects her despite showing the coin and mentioning their prior association. He informs her that there is no one by that name here. Before shutting the door on her face when Arya shouts that she has nowhere else to go. Arya waits outside the headquarters for days, at times through pouring rain, but eventually tosses away her coin and wanders off into the streets of Braavos. Some time later, while hunting for pigeons in the city, Arya encounters several boys who intend to take her sword ‘Needle’ from her. She is saved by the same Faceless Man she met at the door and follows him back to the House of Black and White. Before the gates of the building, the man then assumes the visage of Jaqen H'ghar. However, he insists he's not Jaqen H'ghar, but "no one,” as all Faceless Men are, and he tells Arya she must learn to be "no one" as well.

Some days later, as Arya cleans the main sanctuary of the House of Black and White. The atrium is lined with statues of many gods from many different faiths, from across the continents of Essos and Westeros alike. Specifically, they are gods that represent death and the unknown, such as the Stranger from the Faith of the Seven, the Westerosi gods Arya’s mother Catelyn used to follow. The Faceless Men believe that all of these death gods are really one god who has revealed themselves to humanity in different ways: the Many-Faced God. The sanctuary has a large pool in the center and Arya watches the man who looks like Jaqen H’ghar assist another man in drinking from the temple's well. When the man leaves to pray, Arya tells Jaqen that she wants to learn. He recites the phrase "Valar Dohaeris,” meaning "all men must serve,” and accuses Arya of only wanting to serve herself. When Arya looks back at the praying man, she sees that he has died. Two men then take the man’s body away, ignoring Arya when she asks what they are doing with the body.

Afterwards, Arya is joined in her room by a young woman known as the Waif, an acolyte or religious servant to the Faceless Men. The Waif quickly asks her “who are you?” and elaborates by saying “you, who walk in here with a coin you never earned and whose value you do not respect.” The Waif then asks Arya again who she is, as Arya responds in saying “no one,” assuming that would be the appropriate answer. The Waif then hits here with a large fighting stick as Arya calls her a cunt. The Waif hits her with the stick several more times when Arya continues to give the expected response of "no one." Eventually, Jaqen arrives and demands the Waif to stop. He notices that Arya was about to attack the Waif with ‘Needle’ and points out that Arya cannot be no one, as she is still wearing Arya Stark's clothes and is in possession of Arya Stark’s sword and silver. Realizing his point, Arya later binds her old clothing to a rock and tosses it into a lagoon along with the stolen silver, in order to meet the order's initiation requirements. Too attached to her sword, however, she is unable to discard ‘Needle’ and hides it among a few rocks nearby. Afterwards, as Arya is sweeping the floor, Jaqen escorts her to an inner chamber within the House where she is to help the Waif in stripping and washing corpses. The Waif doesn't respond when Arya curiously enquired what happens to the bodies after they are cleaned.

Some weeks later, Arya continues her training with the Faceless Men as she cleans a corpse methodically, curious of what is on the other side of the door. Arya is about to walk through the door when the Waif obstructs her path. Arya wants to know what happens to the bodies she scrubs clean, but the Waif informs her that she will know when the time is right. Frustrated at the lack of answers, Arya demands to play the “game of faces.” The Waif insists that Arya’s already failed that game and again asks her who she is, to which Arya replies that she is “no one”. The Waif simply instructs Arya to get back to work, as Arya asks her who she is. The Waif tells Arya a story about how she was the only daughter of a widowed lord, who remarried, producing another daughter. Her stepmother then tried to poison her. As result, the Waif sought out the help of the Faceless Men to exact her revenge. The Waif then asks Arya whether she believed the story, surprising Arya. When Arya doesn’t respond, embarrassed that she bought the Waif’s story, the Waif tells her to get back to work, hinting to Arya that to pass the game of faces, Arya must be able to lie convincingly. Later, when Arya is asleep, Jaqen comes to test Arya again. This time, when he asks Arya who she is, she tells him how she came to join the Faceless Men, trying to slip in a few lies into the story. However, Jaqen is able to tell when Arya is lying and hits her with a switch whenever she does. He strikes her repeatedly when she insists that she hated the Hound. Before he leaves, Jaqen asserts that Arya is lying not only to him, but to herself as well.

Shortly thereafter, a grieving father brings his sickly daughter to the temple within the House of Black and White and explains to Arya that he has been to every healer in Braavos and spent every penny he had. He informs Arya that his daughter is suffering and needs to find peace. Arya then sits besides the girl and tells her a short made-up story, about how she was sick too, but her father brought her here and when she drank from the temple's well, she was healed. This persuades the sickly girl to drink the poisoned water from the well. The water gives the peace of a quick death to the sickly girl, and Arya, having successfully proven that she can lie, is then brought to the Hall of Faces with Jaqen H’ghar, a great underground chamber that houses thousands of faces that have been peeled off dead corpses. All of the faces have been taken from the corpses that the acolytes wash in the temple. The Faceless Man then asks Arya if she is ready to give up who she is to become "no one". After a moment of silence, Jaqen then states that she is not ready to become "no one," as she is too attached to her past as a Stark, but that she is ready to become "someone else".

Weeks later, Arya assumes the identity of “Lanna,” an orphan-turned-clam-seller. She demonstrates to Jaqen H'ghar that she can convincingly become a different person, developing an elaborate and very believable backstory. The Faceless Man then sends her, as Lanna, to the harbor and fishing markets where she observes someone Jaqen refers to as "the thin man". A gambler, as Jaqen calls him, that Arya witnesses at the markets refusing a contract to insure a man's boat, leaving the man in desperate circumstances. Jaqen later explains that the thin man's business is a gamble of sorts, yet he does not honor his agreements; when a ship captain dies at sea, he is supposed to make good on his promise to pay the family, but he often doesn't. Jaqen  instructs the girl named Lanna to return to the harbor for a second time to carefully watch the gambler and “get to know him as well as the girl knows herself.” When Arya asks of her instructions beyond that point, Jaqen informs her that she is to kill the thin man, and hands her a "gift" for victim — a vial of poison. As Arya leaves, the Waif asserts her skepticism of Arya’s success to Jaqen. The acolyte asks him what is to happen if Arya is not ready. He cryptically responds by saying “then it is all the same to the Many-Faced God,” implying that there would still be a death served to the gods.

Some days later, “Lanna” pushes her cart through the streets of Braavos selling various types of shellfish. She passes the thin man with intention to poison his purchased oysters from her cart. Just as she reaches him, however, she stops in her tracks, fixated on a boat that has just arrived to Braavos. Stepping out of the boat is Ser Meryn Trant of the Kingsguard, one of the names on Arya's kill list, who assisted in betraying her father Eddard Stark and killed her sword trainer Syrio Forel. She abandons Jaqen’s mission and follows Ser Meryn, who is escorting King Tommen Baratheon’s Master of Coin, Mace Tyrell, to the Iron Bank of Braavos. Afterwards, Arya remains in pursuit of Trant, following him and several guards to a brothel. She sneaks into the brothel under the guise of selling oysters and clams, insisting their benefit as an aphrodisiac. Arya sells a few and then makes her way to the back chambers where she spies on Ser Meryn from behind some shutters. She eventually is chased out by the owner, but not before she learns that Trant prefers sex with very young girls. After returning empty-handed to the House of Black and White, Jaqen asks Arya what happened, as she lies to him, informing that the thin man wasn't hungry and didn't order any oysters. Jaqen quips that perhaps this is why he is a "thin man”. Arya then promises that she will follow through on the assassination tomorrow. She departs, and while Jaqen seems to suspect that she was lying, he makes no outward reaction to it, as Arya will have a lot of work to do soon.

The following evening, Arya triumphantly returns to the Hall of Faces after exacting her revenge and murdering Ser Meryn and discreetly places the face that she used to hide her identity back onto the wall where it was retrieved. However, Jaqen H'ghar and the Waif appear and both assert that Ser Meryn's life was not hers to take, insisting that a debt now must be paid. The Waif then grabs Arya as Jaqen pulls out a vial, presumably containing the same poison he gave her to assassinate the thin man. However, instead of poisoning Arya, Jaqen himself drinks the poison and quickly collapses. Arya rushes over to his body that lies on the ground, screaming for him to stay alive. Amidst her anguished crying and screaming, Arya then ears Jaqen's voice behind her saying “he was no one.” She turns around to see, much to her confusion, that the Waif now has Jaqen's face. Arya asks the Faceless Man who the person on the floor with Jaqen's face is. Jaqen, in the Waif's body, informs again that he is no one. A panicked Arya begins to remove multiple faces from the person on the floor, until she sees her own face. A terrified Arya then starts to lose her sight, as her eyes turn white and, with utter terror, screams for help.

Some time later, the now blind Arya begs for money on the streets of Braavos since losing her sight in the Hall of Faces. After overhearing two passing citizens discussing Ser Meryn Trant’s murder, she is approached by the Waif who is holding two fighting sticks. After remarking on her blindness, the Waif gives her one of the sticks in preparation for sparring. Arya explains that she obviously can't fight because she's blind, the Waif answers "that's not my problem" and starts beating her. Arya poorly tries to defend herself but fails miserably. Unimpressed, the Waif leaves Arya, promising to return the following day. As promised, the Waif returns the following day and asks Arya who she is. When Arya answers "no one," the Waif brushes this off and promptly beats her in another sparring match. Arya angrily lashes out after the Waif leaves her, but is stopped by Jaqen H’ghar, who has been watching her daily. Jaqen repeatedly asks her to say her name. Even after Jaqen’s promise of food and accommodation if she states her name, Arya repeatedly asserts to him that "a girl has no name.” An impressed Jaqen then allows her to return to the House of Black and White.

Later on, the blind Arya resumes her melee combat training with the Waif and Jaqen H'ghar, as she is also tasked to mix potions without sight as well. During her training, Arya continues sparring with the Waif while answering questions about her family, House Stark, as well as a former adversary-turned-traveling companion named Sandor Clegane. Arya admits to leaving the Hound to die instead of killing him, despite wanting his death. The Waif then interrogates Arya about the people on her list: Cersei Lannister, Ser Gregor Clegane and Lord Walder Frey, who was responsible for the Red Wedding massacre that claimed her mother and brother’s lives. The Waif voices her disbelief in Arya’s short list, but she counters by asking which name the Waif wants added. When Arya insists that she is no one, the Waif does not believe her and tries to hit her. However, Arya is able to deflect her blow and leap out of the way, surprising the Waif. After confirming that Arya has mastered blind sparring, Jaqen approaches Arya and offers to give back her sight if she tells him her name. Arya confidently replies that "a girl has no name." Jaqen then leads Arya to the well where he scoops up a bowl of water and offers it to Arya. She is reluctant, as others have drunk from it before and died, but Jaqen insists that if she is truly "no one" there is nothing to fear. Arya drinks from the bowl and her sight is instantly restored. When Jaqen asks Arya who she is, she again replies that she is no one.

Some weeks later, The Waif continues to drill Arya with combat training while never missing an opportunity to attempt in offending her, this time mocking Arya’s high-born origins from Winterfell, stating that she’ll never be “one of us, Lady Stark.”  When Jaqen H’ghar enters the room, he tells Arya that the Waif has a point. Bringing Arya to the Hall of Faces, Jaqen then explains that the first Faceless Men were slaves in Valyria before establishing the Free City of  Braavos and the House of Black and White. As they both look at the faces that hang on the pillars, Jaqen further explains that these were the faces they wore in life when not wearing others. He then states that now “a girl is one of them if she desires.” Arya insists that she doesn’t have any desires. Then handing Arya a vial, Jaqen tells her an actress named Lady Crane will be the next to receive the Many-Faced God’s “gift.” Jaqen warns Arya that she has been given a second chance and won't get a third.

Afterwards, Arya enjoys the spectacle of Braavosi actors re-enacting the War of the Five Kings, playing Baratheons and Lannisters in a play called “The Bloody Hand.” The first scene depicts Robert Baratheon’s indulgence of wine, as Cersei Lannister, played by the actress Lady Crane, asks him to not drink so much, or he will not make good decisions during small council meetings. Robert slaps Cersei and calls such meetings boring. He says he would prefer if Eddard Stark attends the meetings in his stead. Tyrion Lannister is then depicted as having arranged the assassination of King Robert by plying with him more wine before the ill-fated boar hunt. Tyrion then reveals his plans to the audience to dispose of Robert and install Ned as the new king, with Tyrion taking the position of Hand. At the last minute, however, Tyrion reveals the conspiracy by laying sole blame on Eddard. Sansa Stark then begs the good prince, Joffrey Baratheon, to show her father mercy, and he agrees, but Ned gets beheaded after Tyrion bribes the headsman. Arya’s enjoyment of the play ceases when her father, and his execution, are inaccurately caricatured on stage. Eddard also is portrayed as a buffoon and the actress playing Sansa, named Bianca, has her breasts bared to the audience. In further displays of vulgarity, Tyrion pushes Sansa’s hand to his crotch, and announces he will force himself on her during their wedding night. After the performance, Arya sneaks into the dressing room after the play to observe her target, Lady Crane. She appears to be a clever, decent woman, however, Arya later shares with Jaqen her plan to poison Lady Crane’s rum, which no one else in the troupe drinks. Arya suspects that the jealous younger actress Bianca is the one who has commissioned the kill. Jaqen cuts Arya off, however, reminding her that a servant does not question.

Some time later, Arya is watching the second half of the mummers' performance of “The Bloody Hand,” now depicting Tyrion Lannister poisoning his nephew Joffrey and murdering his father Tywin. Arya later walks backstage and poisons Lady Crane's rum, as planned. Upon her exit, Lady Crane notices Arya, and the two briefly converse about the play and Crane’s portrayal of Cersei Lannister. Speaking from experience, Arya suggests that Cersei’s response to the death of her son would not only be grief- it should also include anger. After asking Arya if she likes pretending to be others, Lady Crane tries to express Arya's opinion to the rest of the troupe, but is quickly shut down. Crane then goes to drink the poisoned rum, but Arya slaps it from her hands before she can drink it, blaming the actress Bianca, and quickly runs away. Unbeknownst to Arya, the Waif has been following her and discovers that Arya has failed to kill Lady Crane. The Waif proceeds to report Arya's failure to Jaqen H’ghar, who grants her wish to let her kill Arya, but that she must not let her suffer. Meanwhile, Arya retrieves her sword from its hiding place near the lagoon and makes preparations to defend herself, presumably abandoning the goal of becoming a Faceless assassin and knowing her failure has made her a target.

Following the Waif’s recent attack on Arya, as per Jaqen’s instructions, the acting troupe are once again performing, this time with Lady Crane heeding Arya’s advice in playing Cersei’s loss of her son with more anger. After the scene finishes, Lady Crane walks off stage where she eventually finds Arya in hiding and heavily-injured from the assassination attempt. Afterwards, in Lady Crane’s home, Arya is treated by the gracious actress, who explains her experience in patching up people is due to her proclivity for bad men and violent relationships. When Arya then enquires about the actress Bianca, who ordered the kill, Lady Crane asserts that it will be difficult for the younger actress to find work now after what Crane has done to the girl’s face. With Bianca’s absence from the play moving forward, Lady Crane asks Arya to join the acting troupe, who are next traveling to Pentos. Arya refuses the kind offer, warning Crane of the dangers that will be coming for them if she leaves Braavos. When Crane asks her where she will go, Arya declares her curiosity for lands unknown that lie west of Westeros. Finally, Lady Crane tries to give Arya the milk of the poppy which is rejected at first, but Arya then relents after being told that sleep is the only way for the wound to heal.

The following morning, Arya wakes up, startled by a crash. She finds Lady Crane brutally murdered and the Waif waiting for her. Arya leaps out the window and flees into the streets. She rolls under a wagon and flees into a bathhouse but is unable to outrun the Waif, who is closing in on her. Arya barely manages to stay ahead as she leaps and rolls down a broad flight of stairs, overturning several baskets of vegetables in the process. Arya’s fall causes her wounds to reopen. She then flees into an alleyway and uses her bloody hand to purposefully leave a trail to a doorway, thus luring the Waif into a darkened room that is lit by a single candle. The Waif soon catches up with her. Closing the heavy door, the Waif informs Arya that she can choose to die on her knees or on her feet. Arya rises to her feet and retrieves her sword Needle from its hiding place under a blanket. With one swift slice of Needle, the candle is chopped in half and the room is plunged into total darkness. Afterwards, Jaqen H’ghar enters the Hall of Faces to find a trail of blood. He eventually learns that Arya has murdered the Waif and ripped off her face, sticking it into one of the shelves. Arya has also gouged out the Waif's eyes with her sword. From behind, she confronts Jaqen, who admits sending the Waif to kill her. He then tells Arya that she has finally become "No One" and can now join the Faceless Men. However, Arya corrects him and declares that she is Arya Stark of Winterfell, and that she is going home. Jaqen responds with a nod and a barely perceptible smile as Arya walks away towards her exit from Braavos.

*In the aftermath of her departure, follow Arya's journey throughout the rest of the series.