The Descent

Not to put too fine a point on it, this movie scared the shit out of me. Six women go spelunking, get caved in, and find out that there's something alive down here; of course their group has its own pre-existing tensions, and once things go wrong, they go very, very wrong. One interesting gambit is the film's decision to show the monsters quite clearly (albeit with a tendency to drop shockingly suddenly into frame); another (maybe relatedly) is for the women to give a pretty good account of themselves when fighting for their lives against their subterranean hunters. It's all set up very economically, and almost from the outset is throat-clenchingly tense, punctuated by abrupt 'shock' moments, and ends well too. pfah!