In February 1959, nine Russian hikers ventured into a remote area of the Ural Mountains. Two weeks later, all of them were found dead. What happened is a mystery that has baffled investigators and researchers for decades. It has become known as the Dyatlov Pass Incident. Five ambitious American college students are issued a grant to return to the site of the original events, and they gear up with the belief that they can uncover and document the truth of the incident. But what they find is more shocking than anything they could have imagined.