Jaqen H’gar is an assassin and a member of the much feared Faceless Men of Braavos, an order with the ability to change their faces. Thus, Jaqen H’gar is his assumed name. He claims to be from Lorath, one of the free cities in Eastern Braavos. He had been locked up in King’s Landing and was enlisted by Yoren, the recruiter into Night’s Watch. He leaves with Yoren and others. Yoren also tries to smuggle Ned’s daughter, Arya Stark, out of King’s Landing in the convoy while dressed as a boy.
On the way to the Wall, they are ambushed by Ser Amory Lorch and men from House Lannister, who is in search of Gendry. Yoren is killed for being defiant while Arya helps Jaqen escape from a fire that had caught near the prisoner wagon. They are all captured and taken to Harrenhal.
Jaqen H’gar joins the enemy while Arya is chosen as a cupbearer for Lord Tywin Lannister. For saving him together with two other convicts, Jaqen offers to assassinate three people of Arya’s choosing to repay the debt and also as a tribute to the Red God since they had escaped the fire. Arya chooses the Tickler (a torturer) as her first death who is eventually found dead. Later she is caught going through Lannister documents by Ser Amory Lorch. She runs to Jaqen H’gar and names Ser Amory as the second death. Sure enough, Ser Amory dies seconds before meeting Tywin Lannister. Tywin orders the execution of several men in a bid to uncover the identity of the man who slayed Ser Amory to no avail. He soon leaves Harrenhal thus angering Arya since she wanted to name him as the final death. Arya orders Jaqen to assist her and her friends escape Harrenhal but he refuses. He names Jaqen as the third death, much to his horror, and vows to revoke the wish only if he promises to help them escape. Jaqen H’gar kills all the guards thus aiding Arya and her friends to escape.
Jaqen H’gar is last seen on top of a mountain with Arya. He promises to take Arya to Braavos to become a member of the Faceless Men but Arya has other plans. He gives her an iron coin to give to a Braavosi and utter the term ‘Valar Morghulis’ so as to be given passage into Braavos.
He finally announces that Jaqen H’gar is dead and turns his face away. When he turns to look at Arya again, his face has changed. He bids her farewell, and they part ways.