

An astronaut goes into space with a chimpanzee. When they return to Earth after their orbit, it is discovered that the chimp has the brains of the astronaut, and the astronaut has the brains of the chimp. Complications ensue.
Practical Effects
The chimp costumes are gloriously unconvincing.
Acting
Frankie Avalon commits to chimp mannerisms with alarming dedication.

Director
Norman Taurog
Trivia, insights & behind the scenes
This was Frankie Avalon's fourth and final film with AIP's beach/military comedy factory, desperately trying to keep the formula alive as the British Invasion killed surf rock.
The chimp 'Mr. Mogo' was played by two different chimps—and one scene briefly features a man in a suit when they ran out of animal cooperation.