Actor Anthony Mackie joins Bear Grylls for a journey in the Italian Dolomites mountain range.

"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 takes champion racer Danica Patrick out into the Moab desert for some high-octane, pulse-pounding action in the wild. Together they face off against venomous creatures, sheer cliffs and scorching heat as they make their way across some of the harshest terrain around. Still, nothing is more intimidating than the final challenge that leaves even Danica Patrick unnerved.

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!

As if right out of a science fiction movie, Bear Grylls swoops in on a jetpack to pick up funnyman Keegan-Michael Key, kicking off their adrenaline-pumping adventure in the lava fields of Iceland. The "Key & Peele" star must put all jokes aside to face some of his greatest fears and conquer the lunar landscape. From a perilous rappel off a sheer 200-foot cliff to an endurance-testing jumar climb, Keegan-Michael is pushed beyond mental and physical limits in a truly life-changing experience.

Bear Grylls helps actress Gina Carano face her fears in the Dolomite mountains of Italy.

Bear takes Bobby Bones back into the wild with his new fiancee, Caitlin Parker.