A cop chases two hippies suspected of a series of Manson family-like murders; unbeknown to him, the real culprits are the living dead, brought to life with a thirst for human flesh after government officials conduct pest control experiments using subsonic waves in the area.

After Laura and John Baxter lose their only child in a horrible drowning, they are greeted by strange sightings of her throughout their everyday lives. When two old ladies approach them in Italy with news that their daughter may still be alive, it seems too good to be true. Perhaps it is…