Irish actor Murphy, 47, leads Christopher Nolan’s highly anticipated historical biopic as the theoretical physicist J Robert Oppenheimer, who spearheaded the development of the first nuclear bomb.
Damon, 52, stars as the director of Oppenheimer’s Manhattan Project, Lieutenant Leslie Groves.
Speaking about what it was like acting alongside Murphy, the A Quiet Place star teased that she was often distracted by his eyes while filming.
“It’s a real problem when you’re doing scene work with Cillian,” Damon agreed. “Sometimes you find yourself just swimming in his eyes.”
Blunt compared Murphy’s eyes to Billie Eilish’s 2016 hit “Ocean Eyes”. “We just hum it all day,” she quipped.
“They’re not even that blue!” Murphy exclaimed in response.
Elsewhere in the conversation, Blunt revealed that Murphy skipped cast dinners due to the “monumental” pressure of the lead role.
“We were all in the same hotel,” she said. “We only had each other. Me and Matt were roommates and were like, ‘Let’s go to have dinner.’”
Comparing the environment to “summer camp”, Blunt, however, acknowledged that Murphy’s experience wasn’t so carefree.
“The sheer volume of what he had to take on and shoulder is so monumental,” she said. “Of course he didn’t want to come and have dinner with us.”
“He couldn’t. His brain was just too full,” Damon added.
Jumping into clarify, Murphy said: “You know that when you have those big roles, that responsibility, you feel it’s kind of overwhelming.”
Oppenheimer, which is out in cinemas now, has received rave reviews from critics. The Independent’s Clarisse Loughry called it “clever and imaginative, Nolan at his best” in her near-perfect four-star review.
Writer and filmmaker Paul Schrader, meanwhile, described Nolan’s film as the “best” and “most important film of this century”.
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