Slender Man stabbing

On May 31, 2014, two twelve-year-olds lured their friend, who was also twelve, into a wooded area of Davids Park in Waukesha, Wisconsin, where they attempted to murder and sacrifice her to the Slender Man, a fictional supernatural being originating in creepypasta. Their target, Payton Isabella Leutner, suffered 19 stab wounds, but survived after being rescued by a cyclist.

The perpetrators, Anissa E. Weier (born November 10, 2001) and Morgan E. Geyser (born May 16, 2002), stated they were motivated by their belief in the Slender Man, and believed that killing Leutner would appease him and prove his existence. Weier and Geyser were tried as adults in 2017. Both were found not guilty by reason of insanity, and committed to secure psychiatric facilities. Weier was sentenced to 25 years, and released in 2021 to live with her father. Geyser was sentenced to 40 years and released in 2025 to live in a group home, to be kept under supervision until 2058.

The stabbing generated public debate about the role of the Internet in society and its effect on children, and a moral panic occurred regarding the Slender Man meme. The stabbing inspired the documentary Beware the Slenderman, the movie Mercy Black and several books. In a 2019 interview, Leutner said she was recovering and that the attack inspired her to pursue a career in medicine. In November 2025, Geyser cut off a monitoring bracelet and escaped the group home, only to be arrested in Posen, Illinois the next day and returned to custody.

Background

Morgan Geyser and Payton Isabella Leutner (also known as Bella, a nickname used at the time of the crime) were childhood best friends from Waukesha, Wisconsin. They later befriended fellow Waukesha resident Anissa Weier, who became particularly close to Geyser because they lived in the same apartment building and shared an interest in creepypasta, including the popular supernatural fictional character Slender Man, which Leutner reportedly found frightening. Interrogators were told that Geyser and Weier's obsession with the Slender Man began as early as September 2013.

As their interest in the Slender Man grew, Geyser and Weier believed the character was real and would hurt them and their families if they did not offer him a sacrifice. They planned to kill Leutner to appease Slender Man and prove that he was real. Geyser and Weier had previously planned to kill Leutner, either in her sleep or in a bathroom, but did not carry out either plan.

Events of the attack

On May 31, 2014, during a game of hide-and-seek in heavily wooded Davids Park near Waukesha, Wisconsin, Geyser and Weier pinned Leutner down and stabbed her nineteen times in the arms, legs, and torso with a five-inch-long (13 cm) blade. She suffered two stab wounds to major organs. One wound very narrowly missed a major artery, and another went through her diaphragm, cutting into her liver and stomach.

After the attack, Weier and Geyser told Leutner to lie down while they sought help, which they did not do. Leutner dragged herself to a nearby road, where she was found by a cyclist who called emergency services. Surgeons operated for six hours to treat critical trauma to arteries and tissue in her torso and abdomen. Operating surgeon Dr. John Kelemen said that "If the knife had gone the width of a human hair further, she wouldn't have lived". Leutner left the hospital seven days after the attack. She returned to school in September 2014. In a 2019 interview, Leutner reported lingering trauma from the attack, and said that she sleeps with broken scissors from fear of being attacked again.

Five hours after the attack, police apprehended Weier and Geyser near a Steinhafels furniture store on Interstate 94, approximately 4.9 miles (7.9 km) from the attack location. Police found the knife they used in a bag they were carrying. The children said they were traveling to Chequamegon–Nicolet National Forest, 200 miles (320 km) away, to meet the Slender Man at his home, which they called "Slender Mansion".

Police investigation and pre-trial psychiatric evaluations

During the police investigation and pre-trial psychiatric evaluations, Geyser disclosed lifelong visual and auditory hallucinations starting in early childhood. These typically included figures she interpreted as ghosts, colors melting down walls, and imaginary friends named Maggie and Sev. One recurring hallucination was a man she named "It", whose body was the color of smoke and ink. She perceived "It" as standing behind her in mirrors or shifting around corners.

After Geyser's arrest, her mother, Angie Geyser, described her as becoming "floridly psychotic". Correctional officers reported that Geyser frequently talked to herself, pretended to be a cat, and kept ants as pets. She reported seeing unicorns, and having ongoing conversations with Slender Man and other fictional characters, such as Severus Snape, Lord Voldemort, and one of the Teenage Mutant Ninja Turtles.

In the fall of 2014, Geyser was relocated to the Winnebago Mental Health Institute and was studied there for competency to stand trial. On October 22, 2014, Geyser was diagnosed with early-onset childhood schizophrenia.

Geyser's treatment for schizophrenia was erratic and inadequate for 20 months, which is believed to have exacerbated the psychosis and delusions. In November 2015, Geyser began a consistent, long-term regimen of antipsychotics, which enabled the display of feelings of guilt and remorse toward the crime. On March 23, 2016, Geyser was returned to the county jail to await trial. Although still appropriately medicated, Geyser's mental health further deteriorated, linked to the stressors of forced confinement and incarceration.

During the trial, Geyser was returned to the Winnebago Institute.

Court case and negotiations

Charges and convictions

Geyser and Weier were tried in 2017. Given the nature of the offenses, both were waived out of juvenile court to be tried as adults.

Weier was charged with attempted second-degree homicide, a Class B felony. Weier pleaded guilty to being a party to attempted second-degree homicide. A jury found her "not guilty by mental disease or defect". Weier was sentenced to 25 years, an indeterminate sentence requiring at least three years confinement and involuntary treatment in a state forensic psychiatric institute, followed by communal supervision until age 37.

Geyser was charged with attempted first-degree intentional homicide, a Class A felony. She accepted a plea offer that stipulated she would not undergo a trial if she pleaded guilty and agreed to further psychiatric evaluation to determine appropriate duration of commitment to a forensic psychiatric hospital. She pleaded guilty in accordance with the plea agreement, but was also found not guilty by reason of mental disease or defect, due to her diagnosis of early-onset schizophrenia by court-appointed psychiatrists. She was given the maximum sentence, 40 years confinement in a state forensic psychiatric institute.

Supervised release of Weier

At a hearing on March 10, 2021, Weier (then 19), submitted a letter to the court saying she was "sorry and deeply regretful for the agony, pain, and fear I have caused," not just to Leutner, but to "my community as well". She said, "I hate my actions from May 31, 2014, but through countless hours of therapy, I no longer hate myself for them." On July 1, 2021, Waukesha County Judge Michael Bohren ordered her release from the Winnebago Institute, gave state officials 60 days to draft a conditional release plan, and required that Weier be assigned case managers in the Wisconsin Department of Health Services to supervise her progress until she is 37 years old, the length of her commitment.

On September 13, 2021, Weier was released with multiple stipulations, including 24-hour GPS ankle monitoring that required her to request permission before leaving Waukesha County, and no contact with Leutner until 2039. Leutner's family was "reasonably comfortable" with these restrictions, but wished she had served a longer sentence. Weier's Internet use is restricted and monitored, and she is not allowed to use any form of social media. Weier is required to take court-mandated psychiatric medication and is escorted to regular counseling sessions by a case worker. She is required to live with her father while under supervision. On September 11, 2023, the GPS stipulation was waived.

Supervised release of Geyser

In 2020, Geyser petitioned an appeals court to be retried as a juvenile, but was denied. Her attorney, Matthew Pinix, argued that the charges should have been attempted second-degree intentional homicide rather than first-degree, and that Geyser made statements to investigators before the recitation of Miranda rights. A petition to the Wisconsin Supreme Court to review the ruling was declined in 2021.