"Brooklyn Nine-Nine" star Terry Crews joins Bear Grylls on an epic journey across Iceland's treacherous terrain. Their adventure begins with a heli-ski ride into the mountains, where they must descend a volcanic scree slope without setting off a deadly rock avalanche. Survival is the name of the game for this NFL linebacker turned actor—from trying to cross freezing, violent floodwaters without drowning to finding warm shelter to avoid hypothermia—but nothing can prepare Terry for being tossed out of a plane at 12,000 feet!

Bear Grylls inspires Rainn Wilson to work for it by having him search for hidden caches in the aspen forest and alpine terrain of the La Sal mountains in a time-tested method of mountaineering training. Bear pushes Rainn to the limits of his endurance with dangerous rappels and dizzying climbs, but it's not until they fish for food that things take a revealing turn in what is definitely the most naked RUNNING WILD in the history of the show!