Here's some of overlooked good films of the darker variety. If you like watching "Shawshank" type films, dont' bother with these:
"Damage," staring Jeremy Irons. It's a film about sexual obsession. A high profile English politician falls for his son's wife.
"Requiem for a Dream. Director's Cut." Head and shoulders over "Blow" and "Traffic" in exposing how taking drugs or dealing them can utterly destroy your life. I warn you, this is perhaps the most unpleasant film I have ever seen. It's genius, but I never never want to see it again. A descent into hell.
"Henry: Portrait of a Serial Killer." Another cheery flick that motivated me to buy an alarm for my home. Disturbing, but well made.
"American Psycho." Not a slasher flick but more a commentary on the soulessness of materialism and people in general. There is a sarcastic sense of humor running through this film if you get it...
or care to get it.