For MT Yury Yudin hugging Lyudmila Dubinina as he prepares to leave the group due to illness in late January 1959. The ski expedition's leader, Igor Dyatlov, is watching. Nine experienced cross-country skiers hurriedly left their tent on a Urals slope in the middle of the night, casting aside skis, food and their warm coats. Clad in their sleepwear, the young people dashed headlong down a snowy slope toward a thick forest, where they stood no chance of surviving bitter temperatures of around minus 30 degrees Celsius. Baffled investigators said the group died as a result of "a compelling...