The group heading toward the beacon faces the loss of one of their own if they don't find shelter amidst the sudden snow in the middle of summer. Meanwhile, back at the settlement, Sabina leads the others to the devastated base camp to get clothing for protection against the sudden temperature drop. However, Irene's condition continues to worsen and the situation looks hopeless unless they can get the revealer box open.
In 1908, a meteor hit deep into the remote Siberian territory of Tunguska. Now, more than 100 years later, 16 contestants descend on Tunguska unknowing of the land's mysterious past.
When a contestant is badly injured and no help arrives, the contestants are met with the chilling realization that the strange occurrences are not part of the show. With their safety threatened, competing contestants must band together in an effort to survive.