The Oscar winner kicks off the new season of Running Wild With Bear Grylls: The Challenge, where the survivalist takes Portman to the slot canyons of Southern Utah where the actress learns how to descend various canyons. Only ET has the exclusive sneak peek at Portman in action, where she also reflects on the Marvel experience and returning to wield the mighty hammer in the latest MCU blockbuster.
In the heightened season, Grylls takes the daring adventures up a level by teaching celebrity guests essential survival skills that they will have to master and then prove they can use in a high-stress situation. They'll each be tested on their survival skills beyond other guests: After Grylls teaches each of them a key set of skills, they will then have to master them on their own and deploy those skills at a high-intensity moment to earn their extraction from the wilderness.
Before they hit the ground running on training, Grylls and Portman take a few minutes to discuss her experience being part of the Marvel family. "I pinch myself every day, like this is really, really cool," Portman, who first starred as Jane Foster in 2011's Thor.
The 41-year-old actress spoke about playing the Mighty Thor in Thor: Love and Thunder, nearly a decade after last appearing in the sequel, Thor: The Dark World, in 2013. "I loved that they had it as like a Thor, you know? Thor is a concept, not necessarily a singular person and I'm excited to make a movie that my son likes," she said, referring to her son, Aleph. "He was like, 'Can you keep doing Marvel movies?'"
Portman revealed Aleph's favorite MCU hero -- and it's not Jane Foster! "He loves Doctor Strange a lot," she said with a smile. "And Thor of course."
She also shared that the training regimen to get into shape to play Mighty Thor is intense: "It's super, super physical for Thor... There's also more flexibility in the Thor stuff. You can run and you can swim and you can do weight training. You can mix it all up. It's not quite so specific."
Other celebrities taking on the challenge this season include Ashton Kutcher, Simu Liu, Florence Pugh, Anthony Anderson and Rob Riggle.
Running Wild With Bear Grylls: The Challenge premieres Monday at 9 p.m. ET/PT on NatGeo and is available to stream Wednesday, Aug. 10 on Disney+.
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