Heartless Charlie Babbitt expects a vast inheritance after his estranged father dies. But Raymond, his institutionalised older brother, someone he's been totally unaware of, is willed the entire fortune instead. Raymond is an `autistic Savant' with severely limited mental abilities in some areas but with genius gifts in others. When Charlie kidnaps Raymond, the crazy cross-country drive back to Los Angeles teaches them both a few lessons in life. For as they overcome their mutual distrust of each other, a deep bond is forged as they painfully share past memories, present problems and a possible shining future together.