The film premiered at the Sundance Film Festival in January 2004, and was later screened at the Cannes Film Festival that spring. The film was then given a limited release in major cities on August 20, 2004, mostly playing at art house theaters.

The movie was filmed and set in a small town in Oregon. Small and shy Sam (Rory Culkin) admits to his older brother Rocky (Trevor Morgan) that the school bully, a dyslexic boy named George (Josh Peck) has hurt him, and not for the first time.

Rocky decides along with Sam and his two friends to play a prank on George to get revenge. Rocky's two friends are Clyde (Ryan Kelley), a shy teenager embarrassed by harassment of his gay fathers by Marty (Scott Mechlowicz), the other friend. Marty is an angry and violent young man, traumatized by his father's suicide years earlier.

The boys decide to take George on a boating trip for a "birthday" party for Sam and to then get him to strip in a game of truth or dare, then proceed to make him run home naked.

Sam invites his girlfriend Millie (Carly Schroeder) along, although he does not tell her what they are going to do until they are on their way. Millie refuses to continue until Sam promises him and his brother will call it off, which Sam agrees to do. Sam tells his brother to stop, and Rocky tells his friends what Sam has conveyed to him. Clyde has no problem with it, but Marty refuses to give up. Throughout the trip, George attempts to fit in with the others by telling jokes to the others, which they don't find amusing in the least. However, they begin to sense a desperation in George; he is annoying, but also lonely and wanting to fit in.

They start the ride on the boat and engage in a game of truth or dare. Through a chain of events, George shoots Marty in the groin with a water gun. The others find George's antics funny. George, in a humorous moment with the others after shooting Marty, makes a funny quip about his father, not remembering that it is a sore subject. This sets Marty off, who tells George the whole plan and starts to ridicule him.

Angered, George launches into a tirade against everyone else on the boat, ending by mocking Marty's dead father. Marty snaps and Rocky, in attempt to stop the fight, accidentally pushes George off the boat; it soon becomes obvious that George cannot swim. As the others watch in stunned silence, George accidentally hits his head with his video camera and does not come to the surface. Finally, Rocky dives after him while the others paddle the boat, but he finds no sign of George. Only minutes later he sees George washed up in the shallows, face down. Rocky exhorts the others to help him bring George to shore, where Millie gives him CPR. The effort is in vain as it soon becomes obvious that George is dead.

The kids are terrified, and in a panicked attempt to save themselves, ultimately obey Marty's wish to bury George and then deal with the only witnesses that know they were with George, namely Marty's brother and his friend. Clyde's plan is to explain that it was an accident but Marty threatens them, gaining the complicity of both Clyde and the rest of the group. As they had already tricked George into not telling his mother where he was going, she wouldn't know of their involvement. Marty takes care of his brother and friend, who reluctantly agree to help them.

Marty goes to tell the good news to the friends, who are all at Sam and Rocky's house, but arrives only to find that the group had discussed the situation and decided to turn themselves in. They are willing to accept the consequence, rather than have the guilt of George's death hanging over their heads. Marty however, refuses to turn himself in, getting angry with all of them. He storms out and convinces his brother to give him his gun and car. The brother again agrees to the favor, albeit reluctantly. Marty robs a gas station with the gun and drives off, becoming a fugitive. Meanwhile, the others go to George's house and confess to his mother.

The film ends with the police watching a tape George made of himself talking on his video camera about his dream of becoming a filmmaker.