Williams appears as Arya Stark in the tenth episode of the second season of Game of Thrones, Valar Morghulis. After escaping the Lannister forces at Harrenhal castle, Arya encounters Jaqen H’ghar, Tom Wlaschiha, who is waiting for her outside the stronghold. He offers to ke her to Braavos and teach her the art of assassination so that she can kill her growing list of enemies. Arya refuses and Jaqen H’ghar gives her a coin. He says that if she ever needs to find him again, she must give the coin to a Braavosi and say the words valar morghulis.