Williams appears as Arya Stark in the tenth episode of the third season of Game of Thrones, Mhysa. Rory McCann plays Sandor Clegane, the former Lannister loyalist and kingsguard known as the Hound. At the stronghold of House Frey, the Hound flees the scene of the betrayal of Robb Stark with Arya, who he has knocked unconscious for her own safety. Arya regains consciousness and witnesses soldiers of her brother’s former allies desecrating his body. After escaping, Arya and the Hound come across a group of Frey soldiers in the Riverlands in the center of Westeros. One of them boasts that he was responsible for the desecration of Robb’s corpse. Arya approaches him and tricks him into letting down his guard, before murdering him. The Hound is able to kill the rest of the men, but is stunned at Arya’s actions.