A defrocked priest offers to help an old friend with a sick daughter, but he has no idea what truly awaits him in this story of supernatural horror. The Blackmoor residence rests upon the outskirts of town with a history of magic, mayhem, and death, Jimmy Holiday must decide if the young girl, Lucy, is only ill, or if the haunting of the house and her apparent possession are real. After the house appears to affect him as well with colors of magic dancing before his eyes, rooms warded by a witch, and a ring of power in his voice, Jimmy is met by a transient who tells him he has "the Mark." Whatever being "marked" means, Jimmy doesn't care. All he wants to do is help Lucy. But helping Lucy means performing the one thing he swore he would never do: an exorcism. Will he survive long enough to save the child-and his soul?