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

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.

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.