A strict headmistress runs a secluded school for wayward girls in 19th century France, whose students are disappearing under mysterious circumstances.

A cop chases two hippies suspected of a series of Manson family-like murders; unbeknownst to him, the real culprits are the living dead, brought to life with a hunger for human flesh by ultrasonic radiation being used for pest control.

A teacher who is having an affair with one of his students takes her out on a boat. They see a knife killing on shore. Other gruesome murders start occurring shortly thereafter, and the teacher suspects that he may be the cause of them.