Matt Damon and Emily Blunt admit they were constantly distracted by Cillian Murphy’s piercing ‘ocean eyes’ while filming Oppenheimer

Cillian Murphy’s Oppenheimer co-stars have admitted to being constantly distracted by his piercing deep blue eyes.

Matt Damon, 52, confessed People: ‘It’s a real problem when you do scene work with Cillian. Sometimes you just find yourself swimming in his eyes.”

Emily Blunt, 40, added: ‘It’s like that Billie Eilish ‘Ocean Eyes’ song. We just hum it all day,” to which Cillian, 47, insisted, “They’re not even that blue!”

The film stars Cillian J. Robert Oppenheimer, an American theoretical physicist regarded as the “father of the atomic bomb” for his role in the Manhattan Project – the World War II venture that developed the first nuclear weapons.

Emily Blunt plays Oppenheimer’s wife Kitty, while Matt Damon plays Lieutenant General Groves, the director of the Manhattan Project who appointed Oppenheimer to oversee the development of the atomic bomb.

Co-stars: The film stars Cillian, 47, J. Robert Oppenheimer, “father of the atomic bomb,” Emily Blunt, 40, plays his wife Kitty, while Matt Damon, 52, plays Lieutenant General Groves

Distracted: Matt confessed to People, “It’s a real problem when you’re doing scene work with Cillian. Sometimes you just find yourself swimming in his eyes’

Talking to the New York TimesCillian shared how he needed more than five months before filming to prepare for the role both physically and emotionally.

He confessed that he was “loved” by the physicality of preparing for the role, sharing how he wanted to lose weight to give Oppenheimer a “big eye” to show that he “never ate.”

He said, “I like acting with my body, and Oppenheimer had a very distinct physicality and silhouette, which I wanted to get right.

“I had to lose quite a bit of weight, and we worked with the costume and sizing; he was very slim, almost emaciated, lived on martinis and cigarettes.

“He had really bright eyes and I wanted to give him these big eyes, so we worked a lot on his silhouette and expression before we started.”

While, in an interview with Additionaldescribed Emily — who plays his on-screen wife Kitty — the “monumental undertaking” of slimming down for the part.

She said, “He had such a monumental business. And he could only eat one almond a day. He was so emaciated.’

Hypnotized: Emily added, “It’s like that Billie Eilish ‘Ocean Eyes’ song.” We just hum it all day,” to which Cillian, 47, insisted, “They’re not even that blue!”

In May, Cillian admitted he was “desperate” to land the lead role in Christopher Nolan’s Oppenheimer.

He told the Associated Press, “I’ve always said to Chris publicly and privately that if I’m available and you want me to be in a movie, I’m there.”

“I don’t really care about the size of the part. But deep down, secretly, I was desperate to star him.”

It turns out that Cillian had no idea he was going to get the lead role in Oppenheimer until Nolan called him out of the blue and offered him the part.

“He’s so understated and self-deprecating and just said in his very English way, ‘Listen, I wrote this script, it’s about Oppenheimer.’ I would like you to be my Oppenheimer,” Cillian recalled before adding, “It was a great day.”

Christopher previously told The Hollywood Reporter that casting Cillian in the lead role was an obvious decision.

“I’ve been staring at the cover of the book American Prometheus for so many months, and there’s this picture, black and white, a light blue look, very intense, of this man. And I thought, Well, I know who could do that.