For his latest role, Bradley Cooper leapt onto a hovering helicopter, rappelled down a 400-foot cliff and pulled himself across a 100-foot ravine in one of the harshest climates in North America.

His reward wasn't an Oscar nomination or a big box office hit. It was a hug from adventurist Bear Grylls and some words of encouragement.

"He smashed it," Grylls says.

Cooper is one of several celebrities — including Benedict Cumberbatch, Cynthia Erivo, Russell Brand, Troy Kotsur, Rita Ora, Daveed Diggs and Tatiana Maslany — who put their survival skills to the test in a new season of Nat Geo’s "Running Wild with Bear Grylls: The Challenge," premiering Friday.

"I’m really proud of this season. We’ve had incredible guests who pushed the boundaries in terms of terrain and the challenge," Grylls told The Associated Press. "When there’s real tough weather with fun people, it’s often really compelling TV."

The series pairs Grylls with a celebrity for 48 hours in a harsh environment. The first day, Grylls teaches key skills — climbing techniques, water-finding tips and fire-setting, among them — and then the guest must do them alone the second day.

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Kotsur, who won an Oscar for "CODA," was tested in the Scottish Highlands, descending 2,500 feet across eight miles of harsh terrain and freezing rivers, including a 150-foot rappel down a waterfall. Because Kotsur is deaf, the two men used rope tugs to communicate. Kotsur's reward: haggis, a Scottish delicacy in which organ meat is put inside a sheep's stomach and cooked.

Diggs, a city kid, finds himself in the inhospitable Great Basin Desert in Nevada.

"I don’t know how this is going to go and that’s why I’m doing it," he says. Diggs learns how to use anchor points, track a target and make a signal fire. His dinner is a tarantula.

"It’s not what I was hoping for, I’m not going to lie to you," Diggs says.

Grylls told the AP the best guests are always those who come with a willingness to go with it, not to look good.

"The wild is so unpredictable and stuff is always happening. You can’t look cool all the time in the wild," he said.

The show is not just about survival. Grylls' guests usually open up and show a different side. Ora talks about her ties to Kosovo, Cooper seems unfazed eating mule deer tongue and Cumberbatch reveals stories about his grandfather. Over a campfire, Grylls goes deeper than many TV interviewers.

"It’s as much about the stars and their own personal journeys and struggles and battles as it is about the adventure and the places," he says. "I think that combination works well because it doesn’t feel like a performance, like a chat show does, where you’re dressed up and made up and you get three minutes."

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Cumberbatch is taken to the Isle of Skye, where his grandfather trained as a submariner. He learns how to use climbing talons and how to tie an Italian hitch knot.

"It’s not the same as doing a stunt on a Marvel film. It’s a lot more real," Cumberbatch says. His meal is seaweed and limpets — "Definitely al dente," he jokes — and his bed is a wet field.

Ora arrives at the Valley of Fire in Nevada following a 15,000-foot skydive, learns a chimney climb, butchers a dead pigeon, sacrifices her lip balm to make a fire and uses a sock to soak up water. She and Grylls even dance on a rock ledge, casting their shadows tall.

"The wild strips us all bare, doesn’t it?" Grylls told the AP. "It’s like a grape when you squeeze us, you see what we’re made of. And that’s always the appealing part of ‘Running Wild’ — getting to know the real people."

One commonality among the guests is that viewers will often hear it was the celebrity's parents who instilled in them a sense of adventure and testing themselves.

"It’s a reminder just how important parenting is," Grylls said. "Almost invariably when I ask stars, ‘Where does it come from?’ they go, ‘Oh, my dad was amazing when I was really struggling at school.’ Or, ‘My mum was just such inspiration holding down three jobs.’"

"Running Wild with Bear Grylls" is only one of several shows the adventurist is juggling. On TBS this year, he debuted "I Survived Bear Grylls," a competition series that bridges the survival and game show genres by having regular contestants recreate some of Grylls' stunts — like digging through poop or drinking urine. Younger fans can also enjoy "You vs. Wild," an interactive Netflix show that asks viewers to choose how Grylls will make it out of the wilderness alive.

"I’m not going to be doing these shows forever but hopefully having an adventurous spirit and knowing the value of great friends and the power of a never-give-up attitude in the world — hopefully those things will keep going," the 49-year-old said.

He seems to have tapped into something deep in the human DNA — a need to be able to start a fire, use tools and master the wild. But Grylls thinks it's more than that.

"I really believe it’s a state of mind. We don’t have to be in the wild to live an adventurous life," he said. "It’s how we live our life, how we approach our work, our relationships, our dreams, our aspirations, our interactions with people. Are we leaning on the adventure side? Are we always pushing the boundaries, taking a few risks?"