Two young girls in Wisconsin were arrested this week after allegedly stabbing their friend 19 times, in an elaborately plotted and premeditated attempted murder. The victim is now in critical condition; police say the stab wounds were mere millimeters away from killing her.

Police also say her attackers, both 12-year-old, claimed they tried to kill their friend in order to please "Slender Man," a demon-like character that has been floating through the Internet since around 2009. They thought her death would appease Slender Man, who would appear and let his "proxies" live with him at his mansion in the woods. They thought the sacrifice of their friend would protect their families from him and allow him to come out of hiding. Instead, they are now facing dozens of years behind bars. 

Let's be perfectly clear: Slender Man is not real. He was made up by the Internet, with absolutely no factual grounding. Since his imaginary creation, he has become something between a meme, an urban legend, and a spooky campfire story. The Wire combed through dozens of old forum posts to put together, to the best of our ability, a history of the fictional creature.

In 2009, Something Awful, a humor site with numerous forums known for users with top-notch Photoshop skills and active imaginations created a new thread. The thread asked users to create paranormal images in Photoshop. One user, Victor Surge, created some impressively terrifying images: children with a tall, shadowy, faceless figure, complete with tentacle arms standing behind them. He captioned the images ominously

we didn’t want to go, we didn’t want to kill them, but its persistent silence and outstretched arms horrified and comforted us at the same time . . .
1983, photographer unknown, presumed dead.

Surge's first photoshop of Slenderman. 

Surge said the creation was "pretty spontaneous. I saw some of the pictures in the thread and just decided to make something that I myself would find creepy." Surge went on to make many more images of the sort. He created photographic reproductions, fake news clippings, kids' drawings, and more regular pictures. The popularity of his character, who took on the name Slender Man, encouraged other forum users to create their own pictures.

His captioning also took off. Everyone that made a picture had a scary story to go along with it, each one trying to outdo the other. The captions turned into news clips, book-length stories, gossip posts, and eventually, conversations as if Slender Man were real. 

Eventually, people elsewhere began just writing about Slender Man outside of his original context, and others were soon in on the tale. For those that stumbled onto the story on other websites, they did not know the history, or that what they were reading was fictional. Slender Man has been seen on 4chan, YouTube, Wikipedia, and a site called Creepypasta. There is also a Slender Man Wikia that is quite popular. As he came to new websites, Slender Man's story expanded. To build a following, the e-campfire story tellers were all trying to outdo one another. Some said he had multiple tentacles, some gave him a disfigured face. But the stories that really took off were about Slender Man's power. 

His main power: convincing his "fans" to kill one another, as a protection for themselves. If you kill your friend, you get to protect yourself and your family from Slender Man. Some versions of the story even said that if you killed for him, he would greet you, and take you away to his lair. No one has ever met Slender Man in real life (because, again, he isn't real), so this became a particularly compelling story.

Recently, Slender Man had started to join mainstream media. He inspired the web series "Marble Hornets." Now, Marble Hornets is coming to the big screen. It's going to be filmed as horror movie, directed by James Moran, who is behind the Paranormal Activity films. So, from Photoshop forum to Hollywood.

Surge's second Slender Man.

The story really evolved, because it played into the things we fear most: death, gore, and aliens; all forms of the unknown. Surge said he was surprised it ever became an urban legend from its humble meme-like beginning

In my personal opinion, an urban legend requires an audience ignorant of the origin of the legend. It needs unverifiable third and fourth hand (or more) accounts to perpetuate the myth. On the Internet, anyone is privy to its origins as evidenced by the very public Somethingawful thread. But what is funny is that despite this, it still spread. Internet memes are finicky things and by making something at the right place and time it can swell into an 'Internet Urban Legend'."

The Wisconsin girls learned about Slender Man on Creepypasta, far removed from his Photoshop beginnings five years ago. A Creepypasta admin with the user name "derpbutt" (we told you this is a weird Internet thing) issued a statement on the attempted murder

I’ve been trying to encourage writers here to break out from the serial killers and Slenderman cliches that tend to overrun the Creepypasta fandom, though my motivation was less that I believed Slenderman was harmful [...] I’ve mentioned before that I feel romanticizing serial killers is not really something I feel comfortable with promoting via publishing [...] The families of those affected have my thoughts and prayers, and I hope that you will all join me in extending your sympathy, empathy and respect to them in their time of need and beyond.

The Slender Man Wikia page, which hosts a popular forum and chat room about the character, also issued a statement through their admin Fobarimperius

Slender Man is not a tool or a cop out story for you to use as a flimsy justification for murder, theft, violence, or any other crime. If you ever feel Slender Man is telling you to kill, or you see him in your dreams insisting you kill, we strongly suggest you immediately seek medical attention as not only this is purely insane, it is also completely impossible. If you are a parent who is worried about the potential for Slender Man to scare their child, cause their child to act out, or worried that their child could try to "become a proxy", I strongly urge you to block this wiki's url from your browser and disallow your child any and all access to this site altogether. We all love a good scare, but any real violence is not funny.

While Slender Man has a fascinating digital history, it is important to remember that just like ghost stories and things that go bump in the night, Slender Man is not real. He only exists now as a footnote in a tragic real-life story.