The film takes place at the fictional Camden College, a liberal arts school in northeastern New Hampshire (the film was actually shot at the University of Redlands in California).

The opening sequence introduces the three main characters - Lauren Hynde (Shannyn Sossamon), Paul Denton (Ian Somerhalder), and Sean Bateman (James Van Der Beek), in turn. They are three college students at an "End of the World" party, and although they don't interact at the party, they share a certain apathy about the situations they end up in. Lauren, previously a virgin, is raped while being filmed by a film student who instructs the rapist to sodomize her. The ultimate humiliation culminates when the rapist vomits on her back.

Paul is gay bashed by a jock (Thomas Ian Nicholas) whom he had mistaken for gay (although in the scene it is hinted that he may have been deeply closeted), and Sean recalls (in the third person), "he couldn't remember the last time he had sex sober". After the introduction of each character, time moves backwards until we meet the next character. Essentially we observe the party from three different points of view.

The story then jumps back in time, and for the remainder of the film, we follow the lives of the characters and learn how they came to know each other. Throughout the film, the characters, Sean in particular, exude somewhat of an indifference toward the people and events around them. For example, despite being set at a college, not one of the characters is ever shown attending a class.

At the end of the film, Sean rejects Paul, Lauren refuses to see Sean, Victor doesn't remember anyone, a girl who has been sending Sean love notes commits suicide, and the credits move in reverse, starting with the finish and ending with the cast list.