Mary Gibson, a naive and out-of-her-depth teenager, leaves her private school to search for her missing older sister Jacqueline in New York City. She encounters Gregory Ward, her sister's husband, and Dr. Louis Judd, a mysterious psychiatrist, who claim to know Jacqueline's whereabouts. Unbeknownst to Mary, her sister's disappearance is linked to her involvement with devil worshipers who seek to eliminate her for revealing their existence.

The Seventh Victim
In the heart of New York's Greenwich Village, a desperate search for a missing sister unearths a sinister force, fueling concerns of a Satanic cult's involvement in her disappearance.