Rodney Ascher's (Room 237) latest documentary has its first official trailer, and it's horrifying. The Nightmare follows a group of people who suffer from the terrifying condition known as sleep paralysis. A state between sleep and wakefulness, sleep paralysis occurs when the body is paralyzed, but the mind remains active. As the sufferers lie there unable to move their bodies, visions of shadowy figures - often referred to as 'The Hag' - loom above them, accompanied by physical sensations like a whispering in their ear or tugging on their feet and bedding.

As someone who regularly experiences sleep paralysis, this movie looks utterly terrifying. Ascher uses his first-hand experience with the phenomenon to recreate the sensations of these horrific dreamscapes in vivid detail, exploring the subject from an immersive, personal angle rather than scientific. The Nightmare played at both Sundance and SXSW and received largely positive reviews, with a common thread noting that it functions better as a horror film than an informative documentary. Check out the trailer below.

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NOPE. This is literally the stuff of nightmares. Just watching the trailer made me anxious and gave me that sick tingly feeling in my stomach. But who am I kidding? I will watch this, I will regret it, and I will have all kinds of nightmares. Oh, by the way, they say you're more likely to experience sleep paralysis once you're aware of it. So, uh, you're welcome for that.

Here's the Sundance synopsis for The Nightmare. The film arrives in theaters and on VOD June 5.

THE NIGHTMARE’S subjects hail from different backgrounds and walks of life, but share eerily similar visions of malevolent, near-human beings that grow increasingly aggressive the longer the sleep paralysis recurs. Are these just random hallucinations or something more? Rational explanations get challenged by the similarities of the “shadow people” multiple subjects describe looming over them. Ascher, who has first hand knowledge of sleep paralysis, brings the full intensity of this experience to the screen while maintaining empathy and respect for his subjects. As the film unfolds, distinctions between the documentary and horror genres fade as do easy lines between reality and the imagination.

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