In Haiti, a wealthy landowner convinces a sorcerer to lure the American woman he has fallen for away from her fiance, only to have the madman decide to keep the woman for himself, as a zombie.
Dr. Paul Carruthers is frustrated because he thinks his employers, Mary Heath and Henry Morton, have cheated him out of the company's profits. He decides to get revenge by altering bats to grow twice their normal size and training them to attack when they smell a perfume of his own making. He mixes the perfume into a lotion, which he offers as a gift to Mary and Henry. When they turn up dead, a newspaper reporter decides to investigate.
After her brother's death, Roma Courtney becomes the heiress to his fortune. When a fake psychic claims to have a message from Roma's dead brother, he coaxes her into participating in a séance. While her fiancé first believes the séance is nothing more than a scam, he eventually realizes that the vengeful spirit of an executed murderer has possessed Roma's body.
