‘Beware the Slenderman': Documentary About Wisconsin Stabbing Premieres at SXSW Friday

The HBO documentary, shot over 18 months, features “heartbreaking access to the families of the would-be murderers," according to its description on the SXSW website

The horrific story of how two 12-year-old girls tried to kill their friend to please a fictional horror character on the internet will be explored in a new documentary making its debut at South by Southwest this week.

“Beware the Slenderman,” an HBO documentary directed by Oscar- nominated filmmaker Irene Brodsky, follows the 2014 story of two young girls who are accused of luring their best friend into the woods and stabbing her 19 times to please the fictional character notorious for stalking and terrorizing children.

The documentary, shot over 18 months, features “heartbreaking access to the families of the would-be murderers” and “plunges deep down the rabbit hole of their crime, a Boogeyman and our society’s impressionable consumers of media,” according to its description on the SXSW website.

“The entrance to the internet can quickly lead us to its dark basement, within just a matter of clicks,” the description reads. “How much do we hold children responsible for what they find there?”

Authorities say the girls, who have since been charged as adults, plotted for months to kill their friend Payton Leutner and told investigators they believed Slender Man had a mansion in a Wisconsin forest. They planned to go live with him after the slaying, authorities said.

The girls left Payton for dead after stabbing her more than a dozen times, but she was able to crawl from a wooded area and was discovered by a passing bicyclist. After several surgeries, Payton has returned to school.

Wisconsin law requires attempted homicide cases start in adult court if a suspect is at least 10, but the girls' attorneys have said they hope to see the charges moved to juvenile court, where more services might be available. A judge suspended the case last fall while an appeals court decides whether to review a decision to keep the case in adult court.

The story of Slender Man has provided spooks and thrills for legions of online readers, inspiring a series of videos and once earning the moniker of "the Internet's monster."

The character first surfaced in 2009, when a user on an online forum called Something Awful posted a doctored photo and fictional article in response to a call for fake supernatural images, according to the site KnowYourMeme.com and an expert who has studied the evolution of the Slender Man myth. While such creations aren't uncommon, Slender Man struck a nerve. Soon, users were contributing their own visions of the monster and versions of the terror he'd inflict on unsuspecting school children and others.

In variations of the legend, Slender Man was said to "cause memory loss, insomnia, paranoia, coughing fits," according to Know Your Meme. His narrow frame was accented by tentacles or arms that could stretch and retract in some accounts.

The story spread, inspiring a spin off online video series, video games and threads on various message boards and sites dedicated to scary folklore. It has since become a popular topic on the site Creepypasta, where the two girls charged with the attack reportedly told authorities they encountered the tale.

The documentary makes its debut Friday at the Texas festival. 

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