Clegane is first introduced in the pilot episode when he accompanies the royal court on Robert Baratheon's visit to Winterfell. On the way back to King's Landing, Joffrey falsely accuses a butcher's boy, Mycah, of having attacked him, and Clegane kills the boy, attracting the hatred of Mycah's friend Arya Stark. During the Tourney of the Hand, Sandor's sadistic elder brother Gregor tries to kill Ser Loras Tyrell after Tyrell has unhorsed him, but Sandor defends Loras from Gregor until Robert orders the men to stop fighting. When Ned Stark accuses Joffrey of being a bastard born of incest and orders his arrest, Clegane assists the Lannister soldiers in the subsequent purge of the Stark household and Sansa Stark's capture, although he later comforts Sansa when Joffrey orders her face slapped and advises how to avoid future pain. With Joffrey's ascension to the throne, Clegane is named to the Kingsguard to replace the ousted Ser Barristan Selmy, although Clegane refuses to take his knight's vows.