This engaging 1992 film gives us a pretty good idea of where John Turturro’s manic intensity comes from. Playing a man based on his own father, Turturro is the archetypal blue-collar ethnic guy who gets a wild, frozen look in his eyes just before exploding. At once a labor of love that was 12 years in gestation and an exorcism, “Mac,” which marks Turturro’s directorial debut, is filled with a clear-eyed love and respect. It is about three brothers involved in construction who, in Queens, 1954, make the big leap of going into business for themselves. For Turturro’s Mac there is no conflict between love and work, but the film shows us that the tough perfectionist who can inspire fierce loyalty from his men can also instill massive resentment in his own brothers (Showtime Monday at 3:10 a.m.).