Confessions of a Bad Man

They said he wandered into the emergency room that night, blood streaming down the side of his face. No fracture, they said. What happened? They kept asking him. But he had no answer. That's when his memories start, three weeks ago in the emergency room. He hasn't slept much since.
 
They told him his name is David Willoughby, son of the recently deceased financial tycoon. In the confusion of his traumatic brain injury and amnesia, David wanders into an old bookstore to find a very unusual book, handwritten and illuminated like a medieval manuscript. But this is much older. So David tracks down an expert in the field, Dr. Larissa Fitzgerald to help him decode this ancient tome.

Larissa discovers that David's book is a history stretching back to the eighth century. And it contains spells to conjure demons. Things take a turn when the original owners try to retrieve the book David apparently stole from them. Can Larissa and David save the world from the demons and their allies plotting to empower Evil in the final showdown with the forces of Good?