It's like when you're a kid, bored in class, playing with a rubber band. You stretch it and stretch it, preparing to launch it across the class room and then all of a sudden, totally on its own, it snaps from the pressure and usually hits you straight in the eye and hurts like a bitch.

That's what it's like, pulling and pulling and suddenly having a spirit snapping free.

Sam gasps and reels back but it's-- it's wrong, there's no smoke, just the sensation of pulling, and there's nothing creeping down and through the floorboards. There's no sense of elation, not even vaguely, because he has no idea what just happened and he's physically exhausted.