1944 England. A recovering American serviceman is sent to a remote cottage in Essex where he is instructed to monitor German airwaves. His nightmares of combat haunt him, and his rehabilitation is distracted by the discovery of the half demolished Borley Rectory and something ungodly that is still there. This evil presence follows him back to the cottage and his nightmares overlap into Hell. He calls on Harry Price, the famous paranormal investigator, to come and help him solve the mystery of the nun of Borley.