In February 1959, nine young and experienced hikers set out across the remote Ural Mountains on what should have been a routine expedition - but none of them would return alive. Weeks later, rescuers discovered their tent abandoned and slashed open from the inside, as if the group had fled in absolute terror into temperatures below -30°C. Their bodies were found scattered across the snow - some barefoot, some badly injured, and all surrounded by unanswered questions.