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

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.

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

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

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

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

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

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

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?

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

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.

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.

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

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.

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

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.

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

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

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

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.

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

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.

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.