It was a hot August day in 2014 when Anissa Weier and her friend Morgan Geyser, both 12 years old, lured another 12-year-old girl, Payton Leutner, to a wooded park in the Milwaukee suburb of Waukesha.

There Geyser stabbed Leutner 19 times, while Weier urged her on.

Leuter only survived the attack by crawling out of the woods to a path where a passing bicyclist found her.

Geyser pleaded guilty to attempted first-degree intentional homicide with the agreement that she isn’t criminally responsible and shouldn’t go to prison. She will be sentenced in February, and prosecutors have asked that she be given at least 40 years in a mental hospital. Weier pleaded guilty to being a party to attempted second-degree intentional homicide, but claimed she was not responsible because she was mentally ill. A jury agreed in September and she will spend the next 25 years in a psychiatric institution.

What prompted this psychotic rage by two 12-year-old girls against another?

Hysteria over the fictional character “Slender Man.”

Who is “Slender Man?”

Well, he’s coming to a theater near you in May.

He began as an online myth, a series of doctored photographic images that went viral and developed into a crowd-sourcing fan-fiction project and a frightening, diabolical character to rival the boogeyman and Jack the Ripper combined.

See the trailer for “Slender Man”:

He’s little more than a mysterious tall, gaunt specter with no face, long limbs, always dressed in a black suit and preying on children whom he lures to his hidden den. Depending on who’s spinning the yarn, he could even eat the kids.

He has even become a character in the game Minecraft. But perhaps the most disturbing thing about “Slender Man” is the effect he had on those two 12-year-old girls who have been committed to mental institutions for decades, as well as on the life of Payton Leutner who still has nightmares about the vicious attack they perpetrated on her – and who slept with scissors under her pillow for months, when she could sleep.

The two perps claimed they committed the fiendish crime as a way to get in good with “Slender Man,” whom they believed was real, so he would leave them alone.

Last year, HBO released a documentary on the crime called “Beware the Slenderman.” Now, the character is coming to the Big Screen this spring thanks to Sony Pictures.

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