Teenage Cave Man is a 1958 science fiction film directed by Roger Corman. It was shot as Prehistoric World, but was changed by American International Pictures to its final title (in the UK it was known as Out of the Darkness) and released as a double feature with How to Make a Monster. Years later in an interview, Corman stated "I never directed a film called Teenage Caveman". Lead actor Robert Vaughn has stated in an interview that he considered it to be the worst film ever made. The film was later featured on the television series Mystery Science Theater 3000.
The story revolves around a tribe of primitives in a barren wasteland who struggle to survive, despite a lush environment just on the other side of a nearby river; they refuse to cross the river because of an ancient tale which warns of a god lurking on the other side, who brings death with a touch. A young man of the tribe decides to challenge the law, eventually leading the tribe to follow him across the river and confront the "god": a horribly burnt humanlike giant.
Despite the young man's attempts to make peace, the tribe stones the giant to death. In a surprising and interesting denouement via voice-over by the giant after his death, the truth is revealed: the hideous figure is actually the last survivor of an ancient nuclear holocaust. Surviving due to his radiation suit, he wandered across the land as humanity slowly rebuilt itself, his terrible appearance causing everyone to fear and shun him. The final message of the movie is this: would humanity repeat its mistake?
The film was originally known as Land of Prehistoric Women.