It's the idea. The idea is incredibly original. You have to really enjoy meta horror to like the flick, though. If you watch it as a straight up slasher, it's not going to work. It's a comedy, satire on horror slashers. But it actually gives insight to how characters interact in this environment, and why they do stupid things.
Cabin In the Woods did a similar thing with it, but they took a different approach. Both work. But BTM is a bit more grounded, and has a nice sense of realism.
The ending does pay off, but not in a "HOLY **** WOW!" but more like "
Huh, this is interesting. "
A lot of people don't like meta horror stuff. So it's all up to preference. I found the movie to be funny as hell, with a lot of great nods to classic horror tropes.
I loved the movie up to the point where the girl
Spoiler:starts to do everything that he said the victim would d. If she already knew all the cliches why do exactly that?
I seriously expected the movie to end differently. I didn't expect for her to do exactly what they were making fun of in the movie.
I like the movie but the end ruins it a little bit because of that