An overview of the three “Poltergeist” films details how much of the first film echoed scenes from writer-producer Steven Spielberg's childhood; and how behind-the-scenes difficulties plagued the casts and crews on all three sets. Also detailed are the tragic deaths of Dominique Dunne and Heather O'Rourke. Included: interviews with Spielberg's sister Sue; stars JoBeth Williams, Craig T. Nelson and Zelda Rubinstein; writers Mark Victor and Michael Grais; and directors Brian Gibson (“II”) and Gary Sherman (“III”).