“Slenderman: Online Obsession, Mental Illness, and the Violent Crime of Two Midwestern Girls” by Kathleen Hale

c.2022, Grove Press, $27, 348 pages

Your favorite scary movies almost make you jump out of your skin.

The characters send gooseflesh up your arms, the hairs on the back of your neck rise, and you shiver – admittedly, with delight because a lot of people just like you enjoy having a good scare now and then. You jump – and then you breathe easier, knowing that it’s just a story and, as in the new book “Slenderman” by Kathleen Hale, nobody will ask you to kill.

Though she was an only child and she rarely played with other children at school, 9-year-old Morgan Geyser “was never really alone.” That’s because she had two constant “friends” who stayed inside her head where they lived. She also had Bella Leutner, who was the best friend other people could see, the best friend Morgan always wanted.

In a way, writes Hale, Bella was Morgan’s “caretaker” at school. For three years, she made sure Morgan didn’t do anything rash or self-injurious, and she indulged Morgan’s flights of fancy and “pretended to hear” the same voices in Morgan’s head. But as they grew up, Bella’s social circle grew, while Morgan’s stayed almost the same.

And then Morgan met Anissa, who introduced Morgan to a website that was filled with middle-school-tame stories and tales of murderous beings and alien entities. One of them was called “Slenderman,” who was supposedly 14 feet tall with exaggeratedly long arms and legs, no discernible face, and a penchant for murder.

Within a very short time, both girls became obsessed with Slenderman and decided to become his “proxies.” In order to save their families from sure death, a sacrifice needed to be made; after that, the girls would live with “Slender” in his mansion, which they figured was about 300 miles away from their hometown in Wisconsin.

They’d walk to the mansion to live with Slender forever – but first, Bella had to die....

In her introduction to this book, Hale says that, although she grew up near the area in which the crime happened, she was stymied by a near-total shut-out of information. No one wanted to talk with her except Morgan Geyser, and so Hale mostly used reports, transcripts and public information to craft this book.

Though that could mean a deep sense of familiarity with the story – it may be info you’ve heard or read already – readers will be surprised that the lack isn’t an issue.

The reason, perhaps, is because Hale uses “Slenderman” to delve into the mental health aspect of this incident, peeling it apart from the crime and examining it as a separate subject-within-a-subject. This doesn’t mute the shock of it all – Hale reminds readers many times that the attempted murder was committed by “two little girls” – but it updates and adds another side to a tale that will continue to unfold for decades to come.

This is a book for true crime lovers, but it’s also perfect for anyone who enjoys courtroom dramas, too. If that’s you, then find “Slenderman” and jump on it.