Standing alone outside the Palace nightclub, Steve Fargnoli looked like the saddest man in Hollywood.

He'd devoted two years to bringing Prince's dream, "Purple Rain," to the silver screen. But following the premiere and after-party July 26, 1984, Prince's manager was pessimistic about this maverick rock movie with a first-time star (Prince), first-time director (Albert Magnoli) and first-time producers (Fargnoli and his partners), made in Minneapolis of all places.

I tried to be encouraging, mentioning a few early glowing reviews and the cavalcade of A-list celebs who reacted enthusiastically...