It starts well enough, with some familiar cult faces popping up (Fred from Angel and Josh from the West Wing), switching from the intrigue of "the facility" to the introduction of the inevitably attractive teenage characters. Although at this point I've become bored and started playing Spot the Stiff, for those of you who haven't heard of it, it's where you guess who is going to die based on the cliche they represent. And this film is full of cliches, right down to the Creepy Guy they run into on their way to the titular cabin.
However, it does have odd moments, starting with a bird hitting an invisible force field - this is where I start to realise that this is not a horror film (and then I jump out of my skin when a trapdoor flies open). As the kids go down into the cellar and accidentally raise the dead, this ceases to be horror in my eyes and becomes a parody, where every cliche - trust me, you'll see them - is used to progress a very confusing story, during which comedy seems to be the aim of the game. Not to say it isn't funny, there are some brilliant lines, but it's turned into a waiting game. The audience knows that the real story lies in the government-style facility that seems to be offering up some kind of human sacrifice and that what happens to these kids before they find it is just irrelevant; some will die, some will live, but that's not the point anymore.
An hour in it finally starts to address the issue, with a fun little line that's dropped in about how drugs will protect you from shady organisations, but as it does the film becomes even more ridiculous. One man is killed by a unicorn. It's gone from a vaguely interesting horror parody to a bad version of a fantasy game where every conceivable monster is thrown out to fight, managing to kill everyone bar our protagonists. Why an actress with a reputation like Sigourney Weaver would choose to appear at this point, I don't know. Why the writers, including cult hero Joss Whedon, decided to end this film with a whimper rather than a bang is another mystery. It's comical at best.
If from the start they had decided this was going to be an adventure movie, a parody or even satire, this would have been more appealing, but to advertise this as horror and then hope the audience are interested in the "big twist" was a big mistake, and not really worth a horror fan's time.