Scaroth is determined to go back 400 million years in time to prevent a mistake. But the Doctor must stop him – because the consequences would be disastrous.
Quest roles:
Tom Chadbon(Merdeen), Catherine Schell(Countess Scarlioni), Julian Glover(Count Scarlioni / Scaroth), David Graham(Kerensky), Eleanor Bron(Kara), John Cleese(Art Gallery Visitor)