Chris MacNeil: You show me Regan's double, same face, same voice, everything. And I'd know it wasn't Regan. I'd know in my gut. And I'm telling you that 'thing' upstairs isn't my daughter. Now, I want you to tell me that you know for a fact that there's nothing wrong with my daughter, except in her mind. You tell me for a fact that an exorcism wouldn't do any good. You tell me that!