Finnish director Renny Harlin (‘A Nightmare on Elm Street 4’, ‘Exorcist: The Beginning’) brings a Hollywood sheen to the ‘found footage’ horror movie. Five American students trek into the snowy Ural Mountains, documenting their investigations into the mysterious deaths of nine local Russian hikers in 1959. The early scenes are more slick, but as the group dynamics become more fraught, the filming gets more ragged, until the shaky-cam/night-vision images take over with a vengeance. When not squabbling among themselves, the three young men and their two female companions (British actors Holly Goss and Gemma Atkinson) ponder the cause of the Dyatlov Pass deaths: hyperthermic dementia, fireballs from space and the Yeti are all considered. As things get weirder and scarier, writer Vikram Weet suddenly teleports us into a supernatural realm, where the laws of physics and rational behaviour no longer apply. The students keep filming when it is insane to do so, and an avalanche of speculative tosh smothers everything except our mocking laughter.