On an ordinary school day, a seemingly ordinary student named Leland Fitzgerald (Ryan Gosling) commits a devastating, inexplicable crime ... and everything changes forever ... not only for Leland but his family. friends and the teacher who becomes obsessed with trying to figure out why. Sent to juvenile hall to await trial, Leland says little to clear up the compelling mystery of how a young man of such promise could turn to cold-blooded violence; that is, until he meets Pearl (Don Cheadle), a compassionate but jaded teacher at the prison.

Pearl has never come across anyone like Leland. The son of famous author Albert Fitzgerald (Kevin Spacey), Leland had everything going for him. He seems like the last person on earth who would choose to commit murder, and as smart and insightful as Leland is, the first person to have a clear explanation for what he did. Even more than that, Leland appears to Pearl to be the perfect subject for a novel about the frailty and complexity of the human condition. If he can only get to the heart of what makes this kid tick, Pearl is certain his long-lived dream of becoming a writter as renowned as Albert Fitzgerald will be fulfilled. Defying prison protocol, Pearl arranges to meet with Leland in a series of secret counseling sessions.

The United States of Leland scrutinizes the moral dilemmas at the heart of violence in American society - and reveals how devastation can turn to hope.

As Pearl pushes Leland to disclose the full background of his crime, like a detective, he uncovers as increasingly intricate web of people involved in the story. There are Leland's parents, the intellectually aloof Albert and his wife Marybeth (Lena Olin), who seem as stunned as anyone by Leland's sense of alienation. Then, there is Becky Pollard (Jena Malone), both the victim's sister and the troubled girlfriend who dumped Leland right before the murder, breaking his heart. The victim's family - Including Becky's accomplished sister Julie (Michelle Williams) and her live-in boyfriend Allen (Chris Klein), as well as the murdered boy's parents (Martin Donovan and Ann Magnuson) - bring yet another dimension to the story.

Yet the more Pearl probes, the more clear answers evade his every attempt at understanding. His sessions with Leland soon turn into an aggressive give-and-take, with Leland starting to ask questions of Pearl. Why does Pearl do the immoral things he does, Leland asks? At first, Pearl is angered by this challenge to his authority. Yet he is secretly terrified that he does not have adequate answers for his own actions. Can Pearl really justify any of the things he is doing: cheating on his girlfriend, breaking the juvenile prison's rules, exploiting Leland's delicate, hard-won friendship for a book?

When Leland realizes that Pearl is using him, their relationship comes to a head. Leland's actions continue to ripple through the community, bringing further violence. Yet Pearl now sees that he has a rare opportunity. He may never understand precisely why things went so terribly wrong for Leland Fitzgerald, but he can take inspiration from Leland's biggest regrets and deepest insights to change his own life for the better.