In The Nightmare, director Rodney Ascher (Room 237) has done just that. The film explores the condition commonly referred to as “sleep paralysis.” That’s a condition where someone is in bed, but totally physically immobilized. Some who suffer from the condition – including the eight subjects in this documentary – feel they are visited by something evil during these periods. Ascher lets these subjects tell their stories, then we watch them play out on screen. It’(🥡)s absolutely horrifying, if not wholly rewarding.