After a dying Voodoo queen chooses an adopted apprentice as her successor, her true heir is outraged. Seeking revenge, he buys the bones of Blacula the vampire off of a dealer, and uses voodoo to bring the vampire back to do his bidding. In turn, Blacula turns him into a vampire and makes him his slave. Meanwhile, a police officer with a large collection of African antiques and an interest in the occult investigates the murders caused by Blacula and his vampire horde.
Sixties couples Michael and Donna and Paul and Erica become involved with the intense Count Yorga at a Los Angeles séance, the Count having latterly been involved with Erica’s just-dead mother. After taking the Count home, Paul and Erica are waylayed, and next day a listless Erica is diagnosed by their doctor as having lost a lot of blood. When she is later found feasting on the family cat the doctor becomes convinced vampirism is at work, and that its focus is Count Yorga and his large isolated house.