The two celebrated actors also had a lot of praise for their 'Criminal' co-star, Gal Gadot.
Twenty-five years after the release of Oliver Stone's JFK, the stars of the celebrated political thriller -- Gary Oldman, Kevin Costner and Tommy Lee Jones -- have come together again for the action-packed drama Criminal.
ET recently caught up with Costner and Oldman at a press junket for the crime thriller, where they opened up about their mini JFK reunion.
"We're all grayer," Oldman, 58 laughed. "The one thing I noticed is that we move more slowly than we did, and we make noises when we get out of chairs."
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As for Costner, he could help but gush over working with his famous co-stars once again.
"It was really amazing to see the two of them, and be with them, and watch the three of us," Costner shared. "They're world class actors."
Costner also had a lot of praise for their other Criminal co-star, Gal Gadot, who he called "a good partner."
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"I had never met her," Costner, 61, recalled of their first somewhat-awkward introduction. "I come out of a trailer looking pretty much like Frankenstein almost, and I have to say to her, 'Hi, I'm Kevin Costner,' and she tells me her name, and I said, 'We're going to do a rape scene right now.'"
"But she was a good sport," the two-time Oscar-winner added, "and we were respectful of each other."
Aside from their work together in Criminal, Gadot, Costner and Oldman also share another important film connection: They're all part of DC Comics’ cinematic universe.
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Gadot recently appeared as Wonder Woman in Batman v Superman: Dawn of Justice, while Costner played Clark Kent's adoptive father in 2013's Man of Steel, and Oldman played Commissioner Gordon in all three of director Christopher Nolan's Batman films.
However, the upcoming Justice League film will see another famous face take over the role of Gotham's beloved police commissioner: Whiplash star J.K. Simmons.
Oldman, who said he's "absolutely happy" with that casting choice, gave Simmons his blessing, adding, "I hope he's fantastic in it."
Criminal, which also stars Ryan Reynolds and Alice Eve, hits theaters this Friday.
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