Tenzing director Jennifer Peedom offered the role of Sir Edmund Hillary to Tom Hiddleston because she knew he'd be up for the adventure.
The filmmaker wrote the Avengers star a letter in 2023 asking him to play the New Zealand mountaineer in her movie about Hillary and Tenzing Norgay's successful 1953 Mount Everest ascent.
Explaining why she thought of Hiddleston for the role, Peedom told Cover Media that she felt he had "a willingness and a sense of adventure".
"I watched a lot of interviews from Tom and obviously watched his performance in other films, but read a lot about him," she said. "I could tell that he was somebody who was up for this kind of adventure, which is what I think I said in the letter. But that obviously struck a chord with him. And it was very true - it very much turned out to be the case."
"You don't want to put anyone in a position where you set them up to fail; you want to know that they are going to actually throw themselves into the experience, because I knew that there would be a certain degree of suffering involved in the cold and the way we wanted to do it (practically in the New Zealand mountains)."
Upon Peedom's instruction, Hiddleston and his co-star Genden Phuntsok - who plays the title character Tenzing - went on the trek to Everest Base Camp in Nepal before production began.
The Sherpa filmmaker explained that she asked them to make the trip to forge their own friendship and bring "truthfulness and authenticity" to their performances.
"Because we weren't shooting the film on Everest, we were shooting the mountaineering over in New Zealand, I wanted them to, you know, literally travel in the footsteps of Tenzing and Hillary along those mountain trails, pass those monasteries... and to stand there together and look at Everest for the first time," she continued. "And I think that's an experience that for anyone is going to be life-changing in some ways, and it couldn't help but bond them."
Tenzing, also starring Caitríona Balfe, Willem Dafoe and Thinley Lhamo, will open in select cinemas from Friday before streaming on Apple TV on Friday 16 October.
