This film depicts Brian Wilson trying LSD for the first time during the Smile sessions. In reality, Wilson first dropped acid in 1965, almost two years before the Smile sessions began.
According to Brian Wilson, the argument between Dave and Murry, which led to Dave's departure from the band, actually took place inside of a car.
During scenes in which Brian Wilson (Frederick Weller) is demoing "I Get Around" and "In My Room," the real Brian Wilson contributes the vocal, recorded specifically for this film. However, an uncredited Jeffrey Foskett, a member of Wilson's touring band, provides the high notes during the "In My Room" demo.