A group of teenagers in San Francisco discover a nest of homicidal monsters living in a tower of the Golden Gate Bridge, but when they try to tell authorities, no one believes them.

High school senior Bobby Chrystal fails his French class, which will block him from entering Yale. His rich, authoritarian father hires an attractive 29-year-old to tutor Bobby over the summer and help him pass a make-up exam. While Bobby’s friends lead him away into strange excursions aimed at losing their virginity, Bobby finds all the extracurricular activities he needs with his new tutor.