In the final days of WWI, an allied army unit led by a shell-shocked soldier is sent to investigate a mysterious abandoned German facility located deep underground. What they find is fate worse than death.

Taking place years after The Haunting of Molly Hartley, who now, as an adult, has fallen under the possession of an evil spirit and must be exorcised by a fallen priest before the devil completely takes her.

The police force of a remote Midwestern town search for a killer Santa Claus who is picking off citizens on Christmas Eve.