The film is about the adventure of El Superbeasto, a suave, yet violent exploitation film actor, director and former masked wrestler, and his sultry "sidekick" and sister, the super-agent Suzi-X, as they prevent the evil Dr. Satan from taking over the world by marrying the foul-mouthed stripper Velvet Von Black with the mark of the devil on her backside. The adventure, set in the mythic world of Monsterland, also features Murray the Robot, Suzi-X's sidekick and vehicle, based on the robot featured in the 1939 serial The Phantom Creeps starring Bela Lugosi.