Horror following two college friends who take part in a pharmaceutical experiment during the Christmas break in order to earn some money. The participants are locked up in a secluded hospital during the two week trial but they soon begin to display violent side effects. The doctors are unable to maintain control of the situation and the experiment gets out of hand, putting everyone at risk.

Bret Easton Ellis' disturbing novel is brought to the screen by Mary Harron. In 1987, twentysomething Wall Street broker Patrick Bateman (Christian Bale) seems to have it all: he is handsome, successful and engaged to the beautiful Evelyn (Reese Witherspoon). However, Patrick is also engaged in an affair with Courtney Rawlinson (Samantha Mathis) - his colleague's fiancée - and at night indulges in a confused orgy of drugs, pornography, prostitution and murder fantasies. When Patrick is outshone by a rival at a board meeting, he takes out his frustration by knifing a man sleeping rough in the street. This sparks off a descent into violence and madness, with Patrick embarking on a bloody and random killing spree.