Matt Damon told his wife he would take a break — unless Christopher Nolan called

Matt Damon likes to stay busy.

Over the last couple of years, the actor has starred in Air (which he also produced), The Last Duel (which he produced and co-wrote), and Stillwater, and also made cameo appearances in Thor: Love and Thunder and No Sudden Move. Before Christopher Nolan called Damon to offer him the role of General Leslie Groves in his historical drama-thriller Oppenheimer (out July 21), the actor — who previously appeared in Nolan's 2014 science fiction epic Interstellar — had told his wife, Luciana, that he would take some time off. So how did Damon play the role of Groves in the movie, about "father of the atomic bomb" J. Robert Oppenheimer, without breaking his word? Turns out the actor had secured what future generations may well call "the Nolan exemption" in this spousal agreement.

Wiktor Szymanowicz/Anadolu Agency via Getty Matt Damon at the U.K. premiere of 'Oppenheimer'

"This is going to sound made up, but it's actually true," Damon reveals in EW's Around the Table with Nolan and costars Cillian Murphy, Emily Blunt, and Robert Downey Jr. "I had — not to get too personal — negotiated extensively with my wife that I was taking time off. I had been in Interstellar, and then Chris put me on ice for a couple of movies, so I wasn't in the rotation, but I actually negotiated in couples therapy ­— this is a true story — the one caveat to my taking time off was if Chris Nolan called. This is without knowing whether or not he was working on anything, because he never tells you. He just calls you out of the blue. And so, it was a moment in my household."

"So, even modern psychology has a caveat…" says Downey in the video, which you can watch above.

"For Chris!" says Damon.

"Just checking," says Downey. "You heard it here first!"

Melinda Sue Gordon/Universal Pictures Matt Damon in 'Oppenheimer'

As a result, Damon can be seen in the film playing Groves, the general who oversaw the Manhattan Project, where the United States' atomic weapons were created, alongside costars Murphy as Oppenheimer, Blunt as the physicist's wife Kitty, and Downey as Atomic Energy Commission chairman Lewis Strauss.

Murphy has been a stalwart supporting player in several of Nolan's previous movies, including 2005's Batman Begins and 2010's Inception. But, like Damon, the Irish actor was unaware the director had even written a script about Oppenheimer until Nolan called him up and asked if he was interested in playing the movie's titular physicist.

Melinda Sue Gordon/Universal Pictures Matt Damon and Cillian Murphy in 'Oppenheimer'

"Chris' way of operating is that he just calls you out of the blue," says Murphy. "I genuinely had no idea. He said he was making a movie about Oppenheimer and he said, 'I'd like you to play Oppenheimer.' I had to sit down. It was kind of overwhelming."

Nolan admits that his habit of phoning Murphy without warning to offer him roles does have a downside. "[It's] a fun way to do it," says the director to the actor. "But it means that it's very difficult to call you to go out to dinner or something. Because every time you answer the phone it's like, what's it going to be?"

Oppenheimer hits theaters July 21. Watch the full Around the Table video, with Nolan, Murphy, Damon, Blunt, and Downey above.

EW's Around the Table conversation was conducted prior to the start of the SAG-AFTRA strike.

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