| Director | Al Adamson |
|---|
Wheelchair-using mad scientist Dr. Durea, the last descendant of the original Dr. Frankenstein, works out of a secret laboratory hidden behind the Creature Emporium, a haunted house exhibit located on the boardwalk amusement park in Venice, California.
With the help of his mute, simple-minded assistant Groton, Durea murders young girls for experimentation in hopes of perfecting a blood serum. Durea hopes the serum will heal his paralyzed legs and cure Groton of his condition. A dwarf named Grazbo, the ticket taker at the Creature Emporium, assists Durea and Groton in their crimes.
Count Dracula comes to Durea, promising to help him revive Frankenstein's monster (which he has exhumed from its secret grave in nearby Oakmoor Cemetery) in return for Durea's serum, which he hopes will grant him the ability to go out in the sunlight, thus making him invincible.
The duo brings the monster back to life. Durea sends him and Dracula out to murder his old rival Dr. Beaumont, who both discredited him and crippled him in a laboratory fire.
Las Vegas showgirl Judith Fontaine arrives, looking for her missing sister Joanie who was last seen hanging out with a group of hippies led by Strange. After failing to get help from Sgt. Martin, Judith investigates on her own, attracting the attention of biker Rico and his gang. Rico slips her some LSD at a dive bar with the bartender's help. Judith, on a trip due to the drug, is taken by Strange and his girlfriend Samantha to aging fellow hippie Mike Howard. Mike agrees to help her find Joanie. Judith, Mike, Samantha, and Strange go to the Creature Emporium, which Joanie had been known to frequent. They ask Durea if he has seen her, but he denies it.
More girls turn up missing. The monster kills two police officers while trying to abduct a girl for Durea's experiments. Groton goes to the beach with an axe, kills Rico and his gang before they can rape Samantha, and takes her into Durea's laboratory.
Judith and Mike, who have fallen in love, go to the Emporium, discover the laboratory and confront Durea. He explains that the girls who were killed (including Joanie and Samantha, whom Judith finds preserved in glass-fronted boxes) were frightened before their deaths. This created a special enzyme in their blood, which is the main ingredient for his blood serum. He tells Judith that her fear upon seeing Mike's death will help him complete the serum.
Durea sends Groton and Grazbo after the couple. Grazbo falls through the laboratory's trap door and is killed by impaling himself on the ax he carried. Sgt. Martin and Strange arrive with the police. Groton is shot by Martin and falls to his death from the rooftop of the building. As he attempts to escape, Durea falls from his wheelchair into a guillotine displayed in the Emporium and is beheaded.
Dracula hypnotizes Judith and binds her with rope to a railing. He then confronts Mike, who shoves a lit car flare in the Monster's face, forcing him to briefly turn on Dracula in his pain. Mike unties Judith, and they run away, but Dracula blasts Mike with fire shot out from his ring, burning him to ashes.
Judith faints upon seeing Mike's death. She awakens to find herself bound to a chair in an abandoned and desecrated church in a forest area outside of Venice, where Dracula's coffin is hidden. Dracula is about to drink her blood and turn her into his vampire bride, but the Monster, who has fallen for her beauty, turns against Dracula. The Monster removes Dracula's ring from his finger and forces Dracula out into the surrounding forest. Dracula tears off the Monster's arms and head, but is caught in the sun's rays before he can make it back to his coffin and disintegrates into dust. Judith frees herself and sees Dracula's ashes. She picks up Dracula's ring at the church's door, but, after a flashback of all that has happened to her, drops it and flees in fear.