Bear leads actor Zac Efron on a survival journey into the Northeast Appalachian mountain range.

Actress Courteney Cox joins Bear to maneuver across jagged peaks and descend sheer cliffs on the windswept coast of Ireland.

Actor Sterling K. Brown joins Bear in the high mountains of Colorado, where they battle plummeting temperatures while descending a sheer rock face, track an elusive deer and rappel down a waterfall.

Actor Jesse Tyler Ferguson joins Bear on a 6,000-foot descent along the cliffs and ridges of Croda dei Toni; Ferguson shares insight about his sudden rise to fame.

Oscar-nominated actress Kate Hudson goes on a journey with Bear that involves a treacherous mountain range in Italy; Kate shares details of her unique upbringing.

Singer Nick Jonas accompanies the renowned survivalist on another journey into the wilderness.

Bear takes actor Ben Stiller into the rugged mountains of the Isle of Skye in Northern Scotland.

President Barack Obama and Bear Grylls explore the Alaskan wilderness, where they observe evidence of climate change, sample wild salmon and catkins tea made with water from melting glaciers; Obama discusses his official duties, parenthood and faith.

Bear and NBA legend Shaquille O'Neal are lifted from a freight train via helicopter and whisked away to a dense forest in the remote Adirondacks; they face blood-sucking leeches and a 200-foot rock face as they search for their exit.

Actor James Marsden and Bear venture into the heart of Utah's Rattlesnake Canyon, where they are faced with a chuckwalla lizard.

Bear and actress Julianne Hough navigate the unforgiving terrain and wild animals of the African savanna; Julianne talks about her adolescence and her determination to succeed.

Bear and Super Bowl champion Marshawn Lynch tackle a rugged mountain range that has sharp cliffs and dark chasms; the pair comes face to face with the French Foreign Legion and pursues a wild hog for dinner.

Bear takes former professional football player Deion Sanders to the mesas and canyons of Utah for his first ever camping trip.

Bear and Olympic gold medalist Lindsey Vonn take a speedboat trip, then swim to shore and make their way along a rugged coastline; after traversing a deep chasm, they collect a dinner of sea urchins.

Bear spends two days traveling through Yosemite National Park with actor Channing Tatum.

Actor Michael B. Jordan joins Grylls in Wales where they start their journey by dropping into rough waters off the coast before making their way up the coast and to the top of the mountains for their exit.

Actor Tom Arnold joins Bear in Oregon's unpredictable coastal mountains.

Actor Ed Helms faces sheer cliffs, crumbling rock and a cringeworthy dinner menu while atop Colorado mountains; Helms discusses the road to his career in comedy.

Spice Girl Mel B joins Bear on the two hundred foot cliffs of the Welsh coastline, where a final descent sends Mel into breakdown mode; Bear is stung by a jellyfish, forcing Mel to practice some first aid skills.

Actress Michelle Rodriguez and Bear go to a desert Nevada; unexpected high winds during a sky-diving trip send Michelle off course; Michelle and Bear must come up with clever ways to stay hydrated.

TV host Tamron Hall shares her personal tragedies and triumphs with Bear as they spend two days in the remote Utah desert.

Extreme survivalists go head to head in a race across the Alaska wild. Using ingenuity, experience and just the gear they can carry in their packs, the participants have 60 hours to reach the finish point of each leg of the adventure -- the series features 13 legs -- and in addition to navigating treacherous glaciated river valleys, barren ridgelines, and high mountain peaks, the challengers battle hunger, dangerous predators and unpredictable weather. There is no grand prize awaiting each leg's winner, other than the pride of accomplishing a grueling feat. For season three, the 12 competitors are divided equally into four teams -- Military, Endurance, Alaskans and Lower 48.

Men and women from all walks of life and every corner of the country come together to pursue their common dream of reaching Mount Midoriyama, the world's most notorious obstacle course.

This fish-out-of-water reality series follows four American icons and their dedicated guide as they embark on a hilarious month-long adventure across the globe. As the notorious squad travels to some of the world's most famous destinations, they witness extraordinary moments and discover a whole new world of trouble to get into. From life-changing spectacles to eye-opening cultural experiences to hysterically unexpected twists at every turn, these trips promise to be ones they will never forget.

Wilderness guide and survival instructor Hazen Audel attempts to stay alive in some of the world's most inhospitable places by using centuries-old techniques. Hazen joins tribes in the rainforests of Ecuador, the Kalahari Desert of Namibia, the mountains of western Mongolia, the frozen Arctic of Canada, in equatorial Kenya, and on a remote island in the Pacific Ocean to learn the skills firsthand. He hunts with bows and poisoned arrows, climbs harsh mountains in search of prey, and harvests food beneath shifting sea ice, among other challenges that push him to his limits.