One day in the fictional town Hillside in Southern California, the supplier of prescription medication to the students at the local high school, Troy Johnson (Josh Janowicz), commits suicide. Troy's friend Dean Stiffle (Jamie Bell), who found the body, is prescribed more antidepressants by his father Bill (William Fichtner), a psychiatrist. When Dean returns to school, he is antagonized by drug dealers Billy (Justin Chatwin) and Lee (Lou Taylor Pucci), who were supplied by Troy. Their friend, Crystal Falls (Camilla Belle), flirts with Dean, but he soon realizes that her true intentions are for Dean to retrieve the remaining drugs in Troy's home and give them to her, Billy and Lee, and he refuses to cooperate. To force Dean to procure the drugs, Billy and Lee plan to kidnap Dean's brother, Charlie (Rory Culkin), as a ransom, but they end up kidnapping Charlie Bratley (Thomas Curtis) instead of Charlie Stiffle.