Nine hikers led by a one Igor Dyatlov were crossing the Ural mountains in 1959. None of them survived, though the real mystery surrounding their deaths is why it appeared that they tore their tent apart from the inside before bounding out into the −22 °F night air barefoot, and why several of the bodies had broken ribs and fractured skulls despite no corpses showing signs of struggle. Several of their clothes were highly radioactive, and one doctor declared that no human being could have caused the injuries that killed at least two of the hikers.

We've come to know it as the Dyatlov Pass Incident.

It's the kind of unexplained event that instantly sends your mind to horror movie territory. That's why it's kind of surprising that it's taken this long for someone to actually turn it into a horror movie. But it's finally happening, and that man is none other than Deep Blue Sea, Cutthroat Island and future Hercules 3D director Renny Harlin. The film is creatively titled The Dyatlov Pass Incident and it's about a group of modern-day filmmakers who go to the Dyatlov Pass to make a documentary about what happened to the hikers. As you can no doubt guess, history repeats itself.

Well, history partially repeats itself.

We found the first full international trailer for the film online, and you can watch it without fear of spoilers. However, we also found a behind-the-scenes video that shows... let's just say that it shows something that isn't part of the official record of what happened that fateful night in the Ural mountains over 50 years ago.

And here's the potentially spoilery stuff:

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