EXCLUSIVE: White Horse Pictures and Homegrown Pictures have teamed on Fifth Beatle, a documentary feature about the legendary musician and genius keyboardist Billy Preston. The title refers to a nickname for Preston, the only non-member ever to be credited on a Beatles recording. He had plenty of his own hits and co-wrote the song Joe Cocker made famous, You Are So Beautiful. Fifteen years after his death in 2006, Billy Preston was inducted this past weekend into the Rock & Roll Hall of Fame.