Sheik is a mysterious and agile character who appears in the Legend of Zelda series, specifically in 'The Legend of Zelda: Ocarina of Time.' Sheik is the alter ego of Princess Zelda, adopted to hide from Ganondorf and assist Link on his quest. Disguised as a member of the Sheikah tribe, Sheik provides Link with guidance, wisdom, and various songs that are crucial to progressing through the story. Sheik's true identity is a key plot twist in the game.