Astronauts Alan Virdon and Peter Burke crash land on a strange planet. After being rescued by a friendly human, Virdon and Burke discover this planet is ruled by intelligent apes. To their horror, they discover that they are back on Earth in the year 3085.

Burke, Virdon and Galen come across two humans fighting and get involved, but lose the magnetic disc. To recover it, they must approach the nearby village, where the ape prefect pits humans in a series of gladiatorial games.