Charlie Babbit is a self-centred Los Angeles-based automobile dealer/hustler/bookie who is at war with his own life. As a young teenager, he used his father's 1948 Buick convertible without permission and as a result went to jail for two days on account that his father reported it stolen. It is then that Charlie learns that his estranged father died and left him from his last will and testament a huge bed of roses and the car while the remainder of $3m goes into a trust fund to be distributed to someone. Charlie is pretty angry about this and decides to look into the matter. It seems as if that 'someone' is Raymond, Charlie's unknown brother, an autistic savant who lives in a world of his own at the Walbrook Institute. Charlie then kidnaps Raymond and decides to take him on a lust for life trip to the west coast as a way to get the $3m inheritance...