Here are the things you should know about The Last Exorcism before you go see it.

1) Despite having his name all over the previews and posters, Eli Roth is merely the producer. It seems like he should ought to make at least a few more movies before all the new people get to attach his name to their work a la Wes Craven.
2) It is shown documentary-style, with the inevitable moments of implausibility that this brings. People carrying cameras just won’t act like this in real life situations, and Blair Witch only got away with it by being the first. That said, I only found myself rolling my eyes at the cameraman a handful of times, which is better than average.

If you can get past those downsides, it’s not a bad little movie. The premise is just about enough to justify the price of admission all by itself: a small town exorcist in the Deep South travels around in response to peoples’ letters about crazy relatives or dead livestock, puts on a nice little show for them as a placebo effect to drive away the “demons” that are vexing them, and goes home with a nice wad of cash. Only, he’s started to feel guilty about the whole thing and is getting out of the business. Not only that, but he apparently feels badly enough about it to expose the chicanery inherent in the whole system by taking a documentary crew along on what will be his last exorcism. You can guess how that turns out, of course, but there are still twists and turns aplenty before the plot is played out to its conclusion, which you may well have a prediction about already. (At least, I’ve never seen a horror-with-camera movie that didn’t end with every single character dead or worse. Have you?)