In Seclusion, a group of friends are slowly killed off while they're at an isolated cabin for a destination wedding.
As this movie is mostly moved by characterization, and there's not that many characters to speak of (eight total cast members, not counting the extras at the beginning), it'd have been really easy for the movie to fail, but actually, it mostly worked out moderately well. While the plot isn't overly creative, the interaction between the characters seemed real and accomplished it's goal.
As for the identity of the killer, that's more a mixed bag. There's plenty of red herrings throughout the film, and while they skirted that with the reveal, things still weren't done as well as they could have been. I don't even know if the killer could have realistically killed those that died, as the time-frame seems off. That's not mentioning a scene prior to the reveal, which seems to contradict what was revealed after. Basically, a few scenes needed tightening up a bit.
Another thing worth mentioning is the music, which seems to be stock violin music. It's difficult for me to explain, but the music sounded really cheap, for lack of a better word.
To end on a positive note, though, most of the actors and actresses did a pretty fine job. Nicole Pacent (who's character I am still mixed on) stole the scenes she was in, Alyson McKenzie Wells did a perfect blonde airhead slut, and while Matthew Wise wasn't remarkable, his character wasn't either, so all's well there. The only problem I had insofar as acting's concerned is Clea Alsip. Throughout the film, she was a sappy newlywed, never missing a chance to tell her new husband that she loves him. I know there are people like that out there, but in the situation they were in, it sort of got on my nerves.
Seclusion isn't going to win any awards, but it was a pleasant enough movie made average by a failure to fully explain a scene or two, and adding in some unnecessary red herrings. All things considered, this probably falls somewhere around being average.