'Slender Man' review: Scare-free horror pic about an internet-based monster

What darkness lies in the dreamy imaginative mind of young girls? That could have been a fascinating theme to explore in “Slender Man,” but director Sylvain White fails to deliver on the interesting premise.

If you’ve heard of the internet phenomenon that is Slender Man, it’s likely from a 2014 incident in Waukesha, Wisconsin, where two 12-year-old girls stabbed a friend 19 times and left her for dead. They told police they were acting as proxies for Slender Man, a character they discovered on a website hosting “creepypasta” ghost stories copied over from other sites.

The true story was covered in the excellent 2016 documentary “Beware the Slenderman,” but the horror adaptation presents the character literally, as a malevolent force that can be summoned with a ritual that’s “The Ring” by way of a slumber party game.

A group of small-town, lightly goth teenage girls stumble upon Slender Man during a sleepover — Hallie (Julia Goldani Telles) jokingly tells her mother, “We’re going to drink vodka and meet guys on the internet,” in the film’s only winking line of dialogue, and that they do. Soon, the friend group is disappearing, and the girls are beset with heinous visions of Slender Man, a tall, faceless man in a black bespoke suit. What does he want?

David Birke’s script doesn’t plumb the depths of what might make Slender Man scary, so the movie isn’t scary at all. There’s no tension and no suspense: even when the girls are panicked and screaming as Slender Man attacks them in their imaginations, we’re constantly yanked back to a fairly normal reality.

“Slender Man” has a moody, atmospheric and often abstract aesthetic. Shot by Luca Del Puppo, with a starkly desaturated palate of browns and grays, it’s sometimes so dark that it’s hard to see. That murky mysteriousness could lend well to the mystery of Slender Man, but instead, White puts Slender front and center. Is Slender Man real, or the figment of an active, internet-obsessed morbid imagination? The film tries to have it both ways, and it ends up with nothing at all.