Police investigate the murders of thirteen-year-old Lucinda Pugh's parents who died in their beds after somebody soaked them in gasoline and set their house on fire in their hometown of Santa Loma, California. All evidence points to Lucinda as the emotionally ill culprit despite lack of motivation on her part. When an exorcist attempts to exorcise her, Lucinda reveals that an alien invasion of Earth is imminent and her parents' murders are just the beginning of a full-fledged assault.