Rodney Ascher’s The Nightmare looks like a very scary documentary. As you can see in this trailer, via Indiewire, the oneiric film examines the ambiguous cause, and petrifying effect, of night terrors and sleep paralysis. Ascher’s previous film, Room 237, collated a bunch of conspiracy theories regarding the “real meaning†of Stanley Kubrick’s classic The Shining, using the theories (which vary in eccentricity) to show how a film can provoke such a wide array of responses in different people. In The Nightmare, Ascher uses horror film techniques to emulate the visceral sensation of sleep paralysis, with terrifying results.