A skeptic when it comes to the supernatural, literature professor William Porter gives no credence to claims that the seaside manor he's just inherited might be haunted. He finds nothing mysterious about his Uncle Horace's death from cardiac arrest. His wife, more attuned to spiritual disturbance, refuses to occupy the main house and lodges elsewhere on the grounds. Then Porter sees a shadowy figure illuminated by the red light of the very writing lamp that shone on the scene of Horace's death. And though not convinced that it is a spirit, Porter knows it is responsible for the rash of murders - first of sheep, then people - that breaks out across the countryside.