Guided by the flute playing of his mute servant Barbado, vampire Khorda arrives on a desolate southern California beach in a coffin that washes ashore. After killing a curious surfer who opens the lid, Barbado drags the coffin to his pickup truck and drives to a rambling mansion hidden in Topanga Canyon. Meanwhile at the town center, dozens of hippies congregate, including a young couple, Rona and Pico, and middle-aged craftsman Pop. When biker Monk tries to pick a fight with Pop at the craftsman’s booth, Pico fights off Monk with a kung fu move that attracts a policeman's attention. Now fleeing the authorities, Monk and his girl friend Esslin join Rona and Pico as they make their way to a hippie community housed at the mansion, where Barbado has lived as a friend to the hippies. The house is filled with a dozen young men and women smoking marijuana, painting and playing music. Soon after, Khorda causes a thunderous storm that blows out all the candles lighting the house while Barbado plays his flute to lull the hippies into submission. The priest-like Khorda then speaks from the shadows, advising them to find purpose beyond living in their altered states. Pico, who refuses the drugs offered to him because he wants more from life, eagerly agrees with the robed stranger. As Khorda preaches that they need a “spark” and claps his hands, the lights turn on. In awe of his powers, the group offer him food, but Khorda says that their food defiles the blood and orders them to purge their house if they want to learn more from him, then mysteriously disappears. Despite Esslin’s enthusiasm for the new guru, when Khorda next appears, a suspicious Monk accuses him of being a fraud. The guru easily convinces the others that he is mystical, prompting them to begin a vigorous cleaning of the house. Soon after, Khorda speaks with Esslin alone, asking her to exchange temporary passions for enduring life with him. Esslin eagerly kisses Khorda; however, seeing that his image is not reflected in a mirror across from them, she lets out a horrific scream. Khorda then plunges his fangs into her neck, making her his first hippie victim. The others hear Esslin’s scream but are trapped in their rooms, having found that all the doors in the house are locked. Meanwhile, Monk returns from a drinking binge in town and is killed by Khorda. When their doors mysteriously open moments later, the group find Esslin dancing in a daze to Barbado beating on a bongo drum in the main hall. Despite Pico’s questions about the locked doors and screams, the others seem unfazed and join Esslin in a frenzied dance. Now seriously worried about Khorda’s power, Pico persuades Rona to leave the mansion with him, but Khorda sends Esslin after them. As Pico tries to resists Esslin's seductive advances, she bears her fangs, terrifying Pico, who falls down a flight of stairs into an underground labyrinth of tunnels. Barbado knocks Pico unconscious, binds his wrists in chains and carries off Rona to certain doom. Khorda then tries to persuade Pico to join him and the others in a life of eternity, but Pico vehemently refuses. Left alone, Pico manages to wrestle his hands out of the chains and finds the room in which Khorda is sleeping in his coffin. Shocked at the sight, Pico stumbles backward and accidentally plunges his hand into a bowl of slugs that bloodies his hands. Within moments Barbado attacks him, but Pico paints a bloody cross on the servant’s face, incapacitating him. Pico then flees to Pop's shop where he hysterically recounts the horrific events, but the sedate Pop believes that Pico has taken too many drugs, even after the proprietor finds his dog dead from a neck wound. Soon after, Pico finds Monk’s dead body near the beach and sees hippies Mavis and Bridey buy groceries in a mute, dazed state, oblivious to Pico's greetings. Pop researches his occult books to identify the pendants the girls were wearing and discovers they are pre-Christian idolatry symbols used by novice vampires as protection against the sun. Pop subsequently convinces a police detective to interview the inhabitants of the house regarding Monk’s death, but Khorda easily convinces the detective that he is running a harmless commune, eating only organic foods and pure water. When Rona agrees with Khorda, a desperate Pico tries to show the detective the wounds he received from Barbado, but Khorda makes them disappear before they can be inspected, forcing Pico and Pop to depart in defeat. Reading through more occult books, Pop and Pico learn that Rona might be spared, because she is more than likely in an incubation period before the bite’s venom has become permanent. Using the tunnels to gain entrance into the house, Pico and Pop watch as the group gather in the main hall chanting a devil’s rite over Rona, preparing her as their blood feast. Suddenly Barbado grabs both men in a choke hold, but Pico manages to escape, falling over the railing into the ceremony. Khorda calls on the vampires to attack Pico, who narrowly escapes into the tunnels with Barbado in pursuit. With tools he finds there, Pico knots a knife to a door handle and then slams the weapon into Barbado’s chest, killing him instantly. Pico fashions a wood stake with another tool, then roams the tunnels in search of Khorda. Finding his coffin closed, Pico plunges the stake through the lid, but to his horror, discovers he has killed Pop instead. Only a few feet behind him, Khorda laughs mercilessly at Pico’s blunder. Throwing the slugs onto Khorda’s face, Pico temporarily blinds the vampire, who falls onto the stake and is stabbed through the heart and killed. Hoping to find Rona alive, a delirious Pico rushes to the sunlit main hall, where all the vampires, including Rona, have disintegrated into piles of ash and teeth.