One night after shopping, Roxy Miller (Marilyn Manning) is driving to a party through the California desert when she nearly runs her car into Eegah (Richard Kiel), a giant caveman. She tells her boyfriend Tom Nelson (Arch Hall, Jr.) and her father Robert Miller (Arch Hall, Sr.) about the giant. Her father, a writer of adventure books, decides to go into the desert to look for the creature and possibly take a photograph of it. When his helicopter ride fails to show up at his designated pickup time, Tom and Roxy go looking for him.