Morgan Geyser, now 22, stabbed her classmate Payton Leutner in 2014 in an attempt to please a fictional entity.
It was a crime that made headlines, not only across North America, but across the world - a vicious attack so disturbing that it was difficult to believe that such a thing could actually happen.
It involved Anissa Weier and Morgan Geyser - two 12-year-old schoolgirls who lured one of their sixth-grade classmates out to a woodland park in Wisconsin before stabbing her repeatedly with a knife.
The senseless attack was reportedly 'dedicated' to Slender Man - a fictitious entity invented on an Internet forum who typically appears as a very tall, thin individual with a black suit and no face.
Geyser, who pleaded guilty to first-degree intentional homicide in 2018, was sent to Winnebago Mental Health Institute where she was determined to be suffering from mental illness.
Weier, meanwhile, had also been sent to a mental health facility but was later released on the basis that she no longer represented a threat to the public.
Now, more than ten years after the stabbing, Geyser - who is now 22 - has been granted release from the psychiatric facility in which she has spent almost half of her life.
The decision came after several previous appeals for release, with Waukesha County Circuit Judge Michael Bohren deciding that she had exhausted all treatment options and was no longer a risk.
"She's done what she's supposed to do," he said. "She appears to have a good attitude."
Psychologists who had worked with Geyser also testified to confirm that she had made good progress.
It was argued that keeping her at the facility any longer would likely be counter-productive.