John Krasinski’s ‘Legs Locked Up’ After Suffering Dehydration During Movie Stunt

John Krasinski experienced a small mishap the day he filmed a major stunt for the new movie Fountain of Youth.

While Krasinski, 45, and his costar, Natalie Portman, sat down with the Today show‘s Savannah Guthrie on Tuesday, May 20, to discuss their Apple TV+ adventure film, the actor admitted that his limp in a scene in which his character jumps onto a moving train was the real deal.

“That was a real limp. That turns out, dehydration is real,” Krasinski said when Guthrie, 54, noticed it when she saw the movie. “My legs locked up and I run like a tin man for a train. And I was like, ‘If I miss the train, I will never get to do this again.’ So I did it.”

“But then you said Coca-Cola solved it,” Portman, 43, pointed out.

“That’s right. Literally, Coca-Cola. All the stunt guys were like, ‘Just drink a Coke!’ And I was like, ‘Really?’ And it worked,” Krasinski responded. “There you go, Coca-Cola.”

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In Fountain of Youth, Krasinski and Portman star as a pair of estranged siblings who reunite to follow in their father’s footsteps as treasure hunters and search for the mythical titlular spring, which is fabled as a source of eternal life. The movie is directed by Guy Ritchie.

“It was kind of like a Jedi mind trick but he just assumed that I could do everything, and he’s so sweet and bubbly,” Krasinski said of working with Ritchie, 56, on the movie.

He added, “So he was like, ‘Johnny, we’re going to have a train that’s going to movie and you’re just going to run at it and jump on the back.’ And then I was like, ‘Oh yeah, when are we doing that?’ And he’s like, ‘We’re rolling. Here we go!’ And you’re like, ‘Okay!’ So there’s an assumption that I was going to do all that stuff.”

Krasinski and Portman’s movie filmed all over the world, including at Egypt’s Giza pyramids and the Austrian National Library in Vienna.

“It was crazy, I think every time we looked over at the pyramids we were just pinching ourselves, it was so nuts,” Portman told Today of filming action sequences in Egypt. “And it was open to tourists, which was wild, at the same time — so there were shootouts and cars exploring and tourists were like, ‘What’s going on?’ ”

Domhnall Gleeson, Eiza González, Stanley Tucci, Carmen Ejogo, Laz Alonso and Arian Moayad also costar in Fountain of Youth, which debuts on Apple TV+ Friday, May 23.