Subtitle: The Name Written in Blood
After Roxy Miller (Marilyn Manning) encounters enormous caveman Eegah (Richard Kiel) while driving down a remote California road, her writer father, Robert (William Watters), heads out to the desert to prove his daughter's claims are true. Once there, Robert is knocked unconscious and trapped in Eegah's cave, where he gains some insight into prehistoric life. But, when Roxy and her boyfriend, Tom (Arch Hall Jr.), come to rescue Robert, Eegah grows fond of the girl and refuses to let her leave.
The film was on the show Mystery Science Theater 3000, episode 506.