In February 1959, nine experienced hikers set out into the remote Ural Mountains of the Soviet Union. Led by Igor Dyatlov, the group was well trained and properly equipped for the harsh winter expedition ahead.

They never made it home.

Weeks later, search teams discovered their abandoned tent on the slopes of Kholat Syakhl — a mountain whose name loosely translates to Dead Mountain. The tent had been cut open from the inside, and footprints in the snow showed the hikers had fled into the night, many of them barefoot and without proper clothing.

What followed only deepened the mystery.

Some of the hikers died from hypothermia. Others suffered catastrophic internal injuries. One victim was found missing her tongue. Investigators were left with more questions than answers, and the official Soviet conclusion offered o ...