The Slender Man is coming.

HBO released the debut trailer for its forthcoming documentary, Beware the Slenderman, based on the harrowing stabbing of then 12-year-old Payton Leutner on May 31, 2014 in Wisconsin.

The grisly non-fatal crime was committed by two 12 year old girls, Morgan Geyser and Anissa Weier, who, after luring her into the woods, brutally stabbed their classmate in the hopes of appeasing a dark, fictitious Internet figure and horror meme known only as the Slender Man.

Directed by Irene Taylor Brodsky, Beware the Slenderman premiered during SXSW in March 2016. The film is scheduled to release in January 2017.

Watch the spine-chilling trailer, above.

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