How the ‘Slenderman’ Meme Drove Two Teenage Girls to Try to Kill

In 2014, two young girls stabbed a friend in the woods 19 times and left her to die. A new documentary examines how mental-health issues and an internet meme drove them to do it.

Photo Illustration by The Daily Beast

Particularly online, the boundary between reality and fantasy can be difficult to discern—and as illustrated by Beware the Slenderman, the result of that blurriness can be deadly. Premiering Monday on HBO (after its theatrical debut at last year’s Tribeca Film Festival), Irene Taylor Brodsky’s documentary has, like the cartoonish specter at the center of its tale, multiple malevolent tendrils. An incisive true-crime drama steeped in issues of myth creation, internet-meme phenomenon, and mental illness, it’s a non-fiction nightmare that understands that, when it comes to terror, made-up spooks have nothing on real-life psychopaths.

Beware the Slenderman begins with shaky-cam footage of a person fleeing a faceless ghoul in the pitch-black woods—faux-verité material that deliberately recalls The Blair Witch Project, and serves as an apt opener for a film rooted in the way make-believe can (and strives to) seem real. Brodsky’s focus is a shocking assault perpetrated by two 12-year-old girls—Morgan Geyser and Anissa Weier—in Waukesha, Wisconsin. Their target was their good friend Payton “Bella” Leutner, with whom they’d spent the prior evening having a post-birthday party sleepover. On the morning of May 31, 2014, Morgan and Anissa lured Bella out to the nearby woods and stabbed her 19 times, leaving her to die. When they were apprehended soon afterward, they confessed to the deed, as well as to the reason they’d done such an unthinkable thing: They wanted to curry favor with the Slenderman.

Who, you might be asking, is the Slenderman? As Brodsky’s doc details through a wealth of YouTube videos, video games, and online fan art and short stories, he’s a lanky, faceless white phantom in a black suit who has wispy tendrils coming out of his back, and lives in a mansion alongside his “proxies” (i.e., minions). According to legend, Slenderman preys upon children—although why he does so is, like everything else about the character, open to interpretation. This is because the ghoul has no single author; rather, he’s a crowdsourced creation known as a “creepypasta” (i.e., a horror myth conceived online) that began as a figure conceived for a photo contest on the Something Awful forum by Eric Knudsen (using the alias “Victor Surge”) and then spread across the internet like a virus, picking up bits and pieces of backstory and personality traits along the way.

Slenderman is a malleable monster who can be fashioned into any number of forms (and purposes), and that’s undoubtedly the main explanation for his enduring effect on young people, who imagine him as both a grim reaper-style fiend and a goth protector of the lost, lonely, and wounded. Beware the Slenderman paints a fascinating picture of Slenderman’s pop-culture propagation, capturing the way in which he’s become akin to a modern-day Pied Piper, a kindred mysterious figure leading children off into the unknown wild, his intentions unknowable. What emerges is a portrait of the internet as the birthplace of contemporary folklore—a virtual campfire in which disparate users come together to channel, and distill, their fears, anxieties, and dreams into fanciful tales, à la the Brothers Grimm.

Brodsky’s film casts an intriguing, and ominous, light on the function of memes—as well as on their power to entrance, influence, and warp. According to their parents, both Morgan and Anissa were somewhat odd kids growing up, the former lacking empathy at moments when one might naturally expect it (say, while watching Bambi), and the latter so lonely and socially awkward that she’d often spend schooldays in tears. Their friendship was thus seen as a positive development to both of their sets of parents, and as Morgan’s mom confesses, her daughter’s fondness for Slenderman seemed like a natural tween interest, no different from her own adolescent attraction to material like Stephen King’s It.

Beware the Slenderman’s point-by-point recitation of Morgan and Anissa’s premeditated attack, however, confirms that they were anything but average horror aficionados. In harrowing footage of their separate interrogation-room interviews with police immediately after their arrest, both girls describe their actions, and motives, with a calmness and lucidity that’s chilling. They express no remorse, and make no attempt to convince investigators they had been brainwashed or pressured by the other into going through with the stabbing. Their testimony makes clear that they both believed the Slenderman existed, that they had to kill in order to appease him (lest he harm them and their families), and that they were equally responsible. As a result, their ensuing trial is one not about guilt, but about whether they should be tried as adolescents (which would result in possible release from prison at 18) or as adults.

More pressing than that legal issue is the larger question of how, and why, two tween girls—with supportive parents, from seemingly stable homes—could become so convinced of an obvious falsehood that they’d try to take their own friend’s life. With regard to Morgan, the answer is plain: She had, for years, been secretly suffering with schizophrenia, and was plagued by imaginary voices, hallucinations, and delusions. While it stands to reason that her parents should have been more vigilant about monitoring her for signs of this affliction—since her father is also schizophrenic—both are stunned and devastated by the behavior of their child, who by their account was eccentric but not visibly crazy. And it’s inarguable that, to Morgan, Slenderman seemed so real that it didn’t matter if, logically speaking, she knew he was an impossibility. Her condition prevented her from separating fact from fiction.

Anissa, though, proves to be a different story, since expert therapists testify that she isn’t psychotic, sociopathic, or schizophrenic. If that diagnosis is true, how does one explain either her certainty about Slenderman, or the crime she committed? On that subject, Beware the Slenderman is at a loss, as are her parents. In interviews, Anissa’s grieving father implies that he holds the internet responsible for distorting his progeny’s worldview. Yet on the basis of the material at hand, the online world’s ability to corrupt is limited to those who are already, in some way, psychologically damaged, unwell, or unhinged. Far more than the Slenderman himself, it’s the incomprehensibility of Anissa’s homicidal thoughts and motivations—and the void of reason or compassion lurking within her—that truly makes Brodsky’s film a work of unnerving horror.