The Doctor battles the assassin inside the matrix dreamscape, while the Master tries to bring about his death in the real world.

On a nameless planet in the far future where invisible monsters prowl, the Doctor befriends a warrior woman named Leela, recently banished from her tribe, the Sevateem. She and everyone recognize the Doctor immediately. He is the Evil One who, in their mythology, holds their god Xoanon prisoner and must be destroyed.