“He’s like, ‘You’re gonna spend the rest of your life trying to get that weight off,’” Josh Hartnett recalled
is sharing the “unhelpful” piece of advice that gave him while filming .
During a July 24 appearance on The Tonight Show, the 46-year-old actor told host about how Damon, 53, urged him not to gain weight for his role in the film — after he already made the transformation. Hartnett portrayed nuclear physicist Ernest Lawrence in the Oscar-winning movie.
“[Matt] gave me a lot of good advice. [But] one thing that was just so unhelpful: he told me not to gain the weight I’d already gained for the role,” he said. “I gained about 30 pounds for the role, and he was like, ‘You’re never gonna get that off again, man.’”
Hartnett added that Damon — who portrayed Lt. General Leslie Groves in Oppenheimer — has one rule when it comes to his starring in a film: “Don’t gain weight over 40.”
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“He’s like, ‘You’re gonna spend the rest of your life trying to get that weight off and it’s never gonna come off because your body’s gonna want to get that weight back on. You’re just gonna keep growing back out to that size, and you’re going to try and get it off, but it’s just gonna go back,’” Hartnett explained. “And he kept telling me, like, over the course of the production.”
“I was like, ‘Thanks, Matt. Thanks for telling me this now. I’ve already gained it,’” he quipped. “And now I don’t eat anymore.”
Hartnett and Damon star in Oppenheimer alongside , , , and more. The — which earned $976 million at the worldwide box office — centers on the creation of the atomic bomb during World War II. More specifically, it follows , the man responsible for making the Manhattan Project a success.
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