Earning a reported $2.5 million for his writing services on a big-budget motion picture, Patrick Sheane Duncan is a writer, producer and director at the top of his game. He has proven adept at both substantive, thoughtful dramas ("Mr. Holland's Opus" 1995), action thrillers ("Nick of Time" 1995) and a combination of the two, ("Courage Under Fire" 1996).The son of migrant fruit pickers, Duncan had his first brush with show business as a lad in Los Angeles: as a shoe shine boy one of his regulars was a movie theater manager who would pay with passes to the current films playing. After his father