‘Slender Man’ Teen Morgan Geyser May Have Faked Mental Illness To 'Get Away With It'

The Slender Man stabbing will go down in American history as one of the most brutal and controversial crimes of the 21st century.

OK! readers know that in 2014, 12-year-old students Anissa Weier and Morgan Geyser cornered and brutally stabbed their classmate Payton Leutner in the forest. When asked why they did it, the girls claimed they were trying to prove their loyalty to fictional character Slender Man.

Miraculously, Leutner survived.

While the school girls immediately admitted to their crimes, investigators later discovered they suffered from mental issues which essentially caused their vile killing spree. Weier was sentenced to 25 years of mental health treatment, while Geyser was sentenced to 40.

Now, five years later, REELZ’s new docuseries, Slender Man Stabbing: The Untold Story, is looking back at the girls’ horrific crime and troubling case.

“It’s one of the most violent acts I’ve seen,” says assistant district attorney Kevin Osborne in the show teaser.

“I didn’t allow her to have contact with her parents,” recalls detective Michelle Trussino.

“She was an unmedicated, mentally ill child,” says Geyser’s attorney, Anthony Cotton.

“This was a 12-year-old girl that suffered from a disease she didn’t ask for, she didn’t know she had…” explains trial consultant Rob Rosenberg.

“Or she created a mental illness, so she could get away with it,” adds detective Tom Casey. “I think she’s very dangerous.”

“Morgan Geyser, we want you to make the jury feel as sorry for her as they do towards the girl who got stabbed,” says trial consultant Amy Singer. “How do you punish someone for having a disease?”

Geyser was offered her plea deal after attempting to slaughter Leutner.

“Will I regret giving you this information later?” she is heard telling a detective in a chilling video from her interrogation room.

Slender Man Stabbing: The Untold Story airs January 26 at 8 ET / 7 PT on REELZ.