The Devil Inside(2012)

Makes great use of what's clearly a limited budget, and delivers on its promises for pretty much all the film... except, for the very last minute. But, the disappointment felt at the end is actually proof that you've been entertained (and quite likely pretty well scared) up to that point, and is largely driven by the desire to see more of what had come before. With a more fulfilling ending this'd be a top-notch horror - beating the 'Paranormal' and 'Emily Rose' films at their own game, to a large extent - but the ending, sadly drops it a couple of notches. But only back down to their level, really. Still worth watching, for sure, but a Director's Cut with an extra bit added on to tie it up, would have helped this film's reputation quite a bit.