Detective Murdoch investigates the death of Emily Fuller whose body is found on the riverbank. They trace her to her home where her husband Jeremiah is completely impassive. The dead woman's daughter Betty says her father has been like this since he had been away recently for a few days. Dr. Grace determines that Emily did not drown, as they had initially suspected, but was strangled by someone with a very large hand. Constable Crabtree thinks he knows what's happened after he finds that Jeremiah is officially dead - he's now a Haitian zombie, risen from the dead. After Dr. Grace finds that a second victim's brain has been operated on, Murdoch thinks he knows who they are dealing with.