After a series of failed attempts to expel a devil demon from 11-year-old Cameron, the Vatican turns to Dr. Ember. A desperate and debatable choice. Not only is the terrible and wheelchair-bound scientist not a believer - in addition he drinks, smokes and swears as Satan himself. But he has two major advantages: his sharp wits and his tireless thirst for vengeance. The demon who now possesses Cameron's body is the same evil being that destroyed his family and put him in a wheelchair to begin with.