Christian Bale is probably one of the most talented actors out there. Some actors play the same type of character most of the time but Bale has some really impressive range and maybe even more impressive than his ability to change his physique for different roles.
In American Psycho, he plays New York Wall Street business man and psychotic serial killer, Patrick Bateman. The movie takes plays during the 80s, when all of the ballers were out there trying to make their dollars. They are very vain individuals in the pursuit of wealth, recognition and even the best business card. Because they are all after the same things, it even becomes hard to distinguish between one person and the next.
Bateman appears to follow the same exact path, except for his secret lifestyle. While he fits right in with the yuppies and is arguably more conceited than all of them, he has a strong disdain for a lot of them and takes out his rage on his friends and random people a like.
While the movie is probably listed as an action/thriller it has some underlying dark comical tones to it. It's a pretty graphic movie, so if blood bothers you, read the book. I couldn't even find a trailer that was mostly appropriate.