Chances are if you went to camp around NYC or the tristate area you’ve heard the legend of Cropsey. He’s one of the definitive urban legends around here that everyone has heard some variation of. He’s the usual scary story to tell in front of a campfire- the psychopath who goes around murdering kids for drinking or doing drugs, sometimes dispatching unwary teens with a hammer or a hook hand. Horror fans might remember that the killer in The Burning was named Cropsy. He killed campers (including Jason Alexander, with a full head of hair!) with a gigantic pair of scissors.

So the legend has definitely gotten around. But residents of Staten Island were shocked to find out that there might be a little more to the myth than first appeared, when back in the 80s young kids started disappearing. Eventually an apparent culprit was found, a strange old drifter named Andre Rand who was living in an abandoned mental institute that he once worked as a janitor.

Now, 18 years later, he’s about to be released for the murder of a young girl, but the man’s troubles are far from over. Almost immediately after he gets out people want to charge him for another murder and put him behind bars again.

This documentary is unique in that it’s basically an investigation into whether he really committed the murders or not. See, he might have just been a convenient scapegoat- there’s no actual evidence tying him to the crime, and he was weird enough to allow parents to sigh in relief when he was arrested. He’s clearly mentally disturbed, but did he commit these horrific murders? The film does its best not to take sides, and the story it tells is absolutely terrifying.

The film would be perfect if it weren’t for one glaringly obvious mistake- the filmmakers put themselves in it for absolutely no reason. There’s nothing more irritating that someone who thinks he’s the next Michael Moore or something, and shoehorns themselves into their film. There’s no need for a personal reflection on the Cropsey myth, as Joshua Zeman and Barbara Brancaccio do a fantastic job interviewing all the key figures from the events- parents and friends of the victims, the cops in charge of the case, prosecution and defense lawyers. Everything works here but the film is cheapened by constantly having the directors talk to the camera and narrate the story.

However, there is one section that benefits from their presence, and that’s when they decide to investigate that abandoned insane asylum in the middle of the night, against all sense and logic. In this moment the film becomes true horror, a real-life Blair Witch Project.

A compelling and fascinating doc to be sure, but a flawed one.

8 out of 10

(This review was based on a critic’s screening at Tribeca. For more check out http://www.cropseylegend.com)