Matt Damon and his wife, Luciana Barroso, “negotiated extensively” in couples therapy about him taking a break from acting — only for him to sign on for “Oppenheimer.”

“The one caveat to my taking time off was if Chris Nolan called,” the Oscar winner explained to Entertainment Weekly Monday.

“This [was] without knowing whether or not he was working on anything — because he never tells you; he just calls you out of the blue.”

While acknowledging that the story “sound[ed] made up,” Damon, 52, clarified, “It’s actually true. … It was a moment in my household.”

His co-star Robert Downey Jr. chimed in, joking, “Even modern psychology has a caveat.”

Damon, who has been married to Barroso since December 2005, plays Leslie Groves in the movie, out Friday.

While promoting the biographical film in Paris last week, the Golden Globe winner posed on the red carpet with daughters Gia, 14, and Stella, 12, as well as 24-year-old stepdaughter Alexia.

Barroso, 46, and the couple’s eldest daughter, Isabella, 17, did not appear to be present at the event.

Damon’s co-star Cillian Murphy confirmed during Monday’s roundtable interview that Nolan, 52, does call “out of the blue” to offer up roles.

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“He said he was making a movie about Oppenheimer, and he said, ‘I’d like you to play Oppenheimer,'” the “Peaky Blinders” alum, 47, recalled. “I had to sit down. It was kind of overwhelming.”

Nolan called his process “fun” — but joked that it does make it hard to set up casual plans.

“It’s very difficult to call you to go out to dinner or something,” the filmmaker said. “Because every time you answer the phone it’s like, ‘What’s it going to be?'”

He and Damon previously worked together on “Interstellar” in 2014.