Is there a genre name for the type of movie like
http://en.m.wikipedia.org/wiki/Devil_(2010_film)?
I've seen a couple of them over the years, doesn't always have to be "who is the murderer", but that's the standard case. Basically a group of strangers thrown into a situation and a small, confined set. Another one where I've forgotten the name was about how after some catastrophe a group of people are trapped / saved in an underground bunker and do all kind of awful things to each other.
I don't know how to search for them, so if someone knows a bunch or even better if there is a term for this kind of story I'd love to hear it.