A young woman and man are drugged into soulless zombies while visiting a sugar plantation in Haiti.
Neil Parker (John Harron) and Madeleine (Madge Bellamy) riding in a coach in Haiti pass a funeral. Bodies are buried in the road to prevent their being stolen. Murder Legendre (Bela Lugosi) takes her scarf. The driver fears zombies, corpses made to work in the fields. Dr. Bruner (Joseph Cawthorn), a missionary, advises them to leave. Charles Beaumont (Robert Frazer) has invited them to his plantation to get married, because he wants the girl. He visits the sugar mill of Legendre, where workers move slowly. Legendre offers him workers, but Beaumont wants Madeleine for a month. Legendre gives him a drug to put in wine.
Beaumont tells the bride he loves her; but she won't go away with him. She and Neil are wedded. Legendre carves a candle. Neil and Madeleine drink. In the cup she sees death and faints as Legendre burns the shaped candle. A coffin is placed in a tomb at her funeral. While Neil is drunk, Madeleine appears and speaks to him as a ghost. Legendre tells Beaumont about his zombies and how he took them. They take the coffin from the tomb. Neil calls to Madeleine and finds the tomb empty. Bruner tells Neil either someone stole her body for a death cult, or she is alive. Bruner explains Haitian law makes drugging a zombie murder, and he wants to catch whoever did it.
Madeleine plays the piano for Beaumont, who realizes her soul is gone. He asks Legendre to bring her back. Beaumont drinks a toast and calls Legendre a devil. Legendre hypnotically controls the butler, who is carried off by zombies. Beaumont says, "Not that!" Bruner and Neil find the castle. Neil sees Madeleine on a balcony and follows Bruner. As Neil enters the castle, Legendre watches Beaumont dying. Neil comes in and collapses. Legendre mentally calls Madeleine, who walks past Neil to him. Beaumont tries to touch her but can't. She is about to stab Neil, when someone stops her. Neil wakes up and follows her, saving her from a precipice. Neil shoots the zombies, but they keep walking and go off the precipice. Bruner knocks down Legendre, and Madeleine smiles at Neil. As Legendre gets up, Madeleine is entranced. Beaumont pushes Legendre over the edge and falls off himself. Neil calls back to life Madeleine to kiss her, and Bruner asks him for a match.
This nightmarish story sustains its eerie mood until the very end when all the evil forces die, and the good ones come back to life. With Beaumont the audience may learn that not every means should be used for illicit and unrequited love.