Bear Grylls takes actor Zac Efron on an adventure-filled trip into the wilds of the Catskill Mountains.

Bear Grylls takes Ben Stiller on an epic adventure of survival through the mountains of Scotland's Isle of Skye.

Hollywood superstar Channing Tatum and Bear Grylls chopper into the wilds of the Sierra Nevada for a high altitude, high stakes adventure.

Comic and actor Tom Arnold heads into the wilds of coastal Oregon with Bear Grylls for an ultimate lesson in survival.

MSNBC anchor and reporter Tamron Hall steps outside her comfort zone to explore the beautiful but brutal desert of southern Utah with the legendary Bear Grylls.

Bear Grylls takes NFL Hall of Famer Deion Sanders into the wild to face his toughest opponent yet: the hills of the desert southwest.

Kate Hudson teams up with Bear Grylls for a harrowing trek across the Italian Alps.

Modern Family star Jesse Tyler Ferguson joins Bear Grylls on a snowy survival trek across Europe's jagged South Tyrol.

Academy award winner Kate Winslet follows Bear Grylls on a harrowing trek through Wales' Snowdonia mountains.

Bear Grylls and Ed Helms copter in to conquer the high country of Colorado.

Fast and Furious star Michelle Rodriguez pushes the boundaries of adventure as she and Bear Grylls journey across the high desert of Nevada.

Bear pushes film star James Marsden to the limit as they trek through the wild canyon country of Utah.

Fantastic Four star Michael B. Jordan braves a pounding surf, towering cliffs and freezing nights as he and Bear Grylls venture through the highlands of Wales.

NFL star Drew Brees heads with Bear to the jungles of Panama for a treacherous trek, filled with snakes, crocodiles and quicksand.

Bear and President Obama venture into the wilds of Alaska, sharing stories and conversing on everything from fatherhood to climate change.

Pop superstar Nick Jonas joins Bear for a thrilling, chilly trek through the snowy mountains of the Sierra Nevada.

Actress, singer, dancer, adventurer? Julianne Hough joins Bear for an emotional and breathtaking journey in the African Savanna.

Bear takes actress Courteney Cox on a harrowing and emotional trek through the Irish Highlands.

The basketball legend joins Bear in the Adirondack Mountains for a strenuous hike filled with laughs and Shaq's witty insights.

Olympic gold medalist Lindsey Vonn joins Bear on a harrowing journey along the Corsican coastline.

America's Got Talent judge and pop icon Mel B roughs it with Bear on the shark-infested waters of the Irish coast.

Super Bowl champion Marshawn Lynch puts his survival skills to the test on a two-day adventure with Bear in Corsica.

This Is Us star Sterling K. Brown steps outside his comfort zone to join Bear on a trek through the icy mountains of Colorado.

In honor of Red Nose Day, Oscar-winning actress Julia Roberts accompanies Bear on a two-day wilderness trek to deliver lifesaving vaccines to a remote Kenyan village.

Vanessa Hudgens joins Bear Grylls on an adventure in the High Sierra.

Actor, writer and director Joseph Gordon-Levitt gets up close and personal with wildlife and reaches new heights on his inspiring two-day trek with Bear through the rugged desert of Kenya's northern plains.

Actress Keri Russell joins Bear on a daring two-day adventure through the unstable terrain of the volcanic Canary Islands off the west coast of Africa, where they tackle steep cliffs and deep gorges before soaring to new heights.

Actress Lena Headey joins Bear on a two-day expedition through the unforgiving landscape of the Iberian Peninsula, complete with steep cliffs and icy waters. Lena's known for playing fierce women, but is she tough enough to survive the wild?

Actor Don Cheadle tackles the unrelenting White Mountains of New England as Bear pushes him to leap outside his comfort zone across rugged and remote terrain teeming with dangerous animals - including the threat of a wild bear!

Dancer and actor Derek Hough joins Bear for a dizzying adventure through Bulgaria's Rila Mountains, where they take on towering peaks and freezing waters and even learn a few dance moves.

Actor Scott Eastwood joins Bear for an exhilarating two-day adventure through an ancient labyrinth of cliffs and treacherous caves deep in the Balkan Peninsula.

World champion tennis player Roger Federer joins Bear for a thrilling match with Mother Nature as they take on frozen waterfalls and towering cliffs - and even find wilderness uses for Roger's rackets - in a memorable trek through the Swiss Alps.

Orange Is the New Black actress Uzo Aduba joins Bear for a heart-stopping adventure in Spain's remote Pyrenees mountains, where steep cliffs, deadly predators and punishing weather test Uzo's mental and physical resolve on a truly wild adventure.

Actress Brie Larson accompanies Bear Grylls on a jungle adventure across a remote island in the Gulf of Panama. They begin their journey by jumping out of a helicopter into the ocean. From there, they make a perilous trek through a crocodile-filled mangrove swamp that turns into a dangerous maze as the tide rises.

The often clever, always snarky actor and comedian Joel McHale joins Bear Grylls in the Arizona desert for an adventure unlike any other. They set out to traverse a massive slot canyon in hopes of surviving the wild, but first they have to survive one another! Huge cliffs, nasty food and unorthodox survival strategies abound in this hilarious misadventure

Actress, supermodel and social-media influencer Cara Delevingne realizes a long-held dream of accompanying Bear Grylls on an adventure. Sweeping Cara off her scooter and onto a helicopter, Bear leads Cara up the mountains of Sardinia. At nearly a mile high in elevation, Bear shows Cara how to brave several heart-stopping obstacles including pulling herself across a horizontal line suspended 200 feet in the air and rappelling down a dangerous waterfall.

Comedic actor Rob Riggle joins Bear Grylls on an adventure on Iceland’s Vatnajokull Glacier. Their journey begins with a helicopter ride over “the land of fire and ice,” aptly named for constant volcanic activity beneath the surface. Once dropped off, Bear and Rob must navigate a stretch of jagged ice fields, deep moulins and deep crevasses. Without food or supplies to make shelter, their mission is to find an airdropped emergency cache.

Golden Globe-nominated actor Armie Hammer pairs with Bear Grylls to scuba dive in search of an underwater sea cave reportedly used by smugglers somewhere off the coast of Sardinia. Along the way, Armie battles his paralyzing fear of heights and samples some local delicacies — and things take an unexpected turn when he gets hijacked in the middle of the expedition.

Bear Grylls takes former WWE world champion and action star Dave Bautista on a super-sized adventure in the Arizona desert. Navigating through perilous canyon descents, brutal falls and the raging Colorado River is no easy task. With Bear as his tag-team partner, Dave is up for the challenge to see if he still has that fight inside, but Mother Nature could prove to be his toughest opponent yet in this match of a lifetime.

It’s been five years since Channing Tatum first appeared on Running Wild with Bear Grylls, and he’s back for more – this time in the wilds of Norway! Their journey kicks off by skydiving into brutal terrain where giant boulder fields and towering cliffs stand in the way of extraction. During their seven-mile trek, Bear tests Channing to see how far he’s come as a survivor – from foraging for food to Navy SEAL-style cold-water immersion training. Channing even learns the ancient art of trout tickling.

Free Solo rock-climber Alex Honnold joins Bear Grylls for a breathtaking adventure through the Swiss Alps! Alex is no stranger to dizzying heights, but he’s not used to falling from them, so Bear kicks off the journey with a skydive into the jagged mountains. From there, it’s a six-mile trek through craggy valleys and sheer cliffs where Bear teaches Alex how to survive in the wild, but the tables turn when Alex takes Bear on a hair-raising climb.

On-air radio personality Bobby Bones joins Bear Grylls for the adventure of a lifetime in a massive Norwegian Fjord! A helicopter ride into the mountains is where their journey begins, but from there, danger lurks at every turn – from giant rock domes and deadly bogs to raging rivers with currents strong enough to move cars. On top of that, the only way to reach their extraction is to rappel down a 300-foot waterfall.

Bear Grylls and actor Zachary Quinto race the clock to traverse a dense Panamanian jungle before an impending storm makes landfall. Their adventure begins with a helicopter ride, but once dropped off deep in the brush, they must rely on a primitive navigation technique to help them reach their extraction point, and it won’t be easy! From massive cliffs and steep ravines to an underground river cave and an old crashed plane, there are obstacles at every turn.

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 takes LA icon and living legend Danny Trejo out into the staggering peaks and steep canyons of Arches National Park in Utah. Under scorching temperatures, Bear and Danny climb massive boulders and traverse sheer cliffs in order to reach their extraction. Even Danny's days in prison can't prepare the show's oldest competitor as he squares off against the intense heat and treacherous obstacles of Mother Nature herself.

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.