Next airing Thu Dec 8, 9 a.m. ET

Hell Hole

The teams will traverse the treacherous Hayes Glacier, then bushwhack through dense forest on their way to the extraction zone 30 miles away. The Mountaineers charge through a glacial canyon and hit what might be a dead end, but expert ice climber Tyler isn't daunted by the 80-foot ice wall. The Endurance team gets a shock when their strategy leads them right to a dangerous 200-foot rappel. Military is making great time until a wrong step drops Grady into the depths of a deadly crevasse.