LOS ANGELES, CALIFORNIA: Robert Downey Jr and Cillian Murphy collaborated on the upcoming Christopher Nolan film 'Oppenheimer'. While they had a good working relationship on set, Downey revealed that there were moments where Murphy was somewhat challenging to work with. Downey enthusiastically accepted the opportunity to be part of Nolan's film, despite being on a break from the film industry at the time that he learned about the project.

In the star-studded cast, including actors such as Emily Blunt, Matt Damon, Florence Pugh and so on, Downey had the opportunity to witness Murphy's remarkable immersion into his role as J Robert Oppenheimer, the father of the atomic bomb. However, Downey admitted that Murphy's portrayal sometimes made him uncomfortable due to the intensity and depth of his performance. Murphy's ability to fully embody the character had a powerful impact on his co-stars.

Did Robert Downey Jr and Cillian Murphy have issues while filming?

"I had been cooling my heels for about a year before the pandemic, just reacquainting myself with my family and other interests because I had been working super consistently," Downey said according to News 18. "But this was Christopher Nolan, doing something that was important to him. The cast was this large gathering of folks who have their choice of projects. And just as soon as we were underway, world events lined up in a way that turned this movie into an important metaphor that could speak to any number of things. So, it was kind of a no-brainer."

"Even just by the time I was on set, seeing how Cillian had embodied this character, to the point where you go like, ‘I’m practically with the guy.’ You can’t help but feel a little bit iced out by it," Downey told Extra TV, continuing, "Now Cillian is so warm and nice and inviting. But then we’d roll, and I’d feel like he was looking through me like I didn’t exist. And I was like, ‘That sucks.'" He added, "I can only imagine it was a lot of people who felt that way."

'I was desperate to play a lead for him'

Cillian Murphy has a history of working with Nolan even before 'Oppenheimer'. He had appeared in all three of Nolan's Batman movies and had notable roles in films like 'Inception' and 'Dunkirk'. However, 'Oppenheimer' marked the first time Murphy was cast in a lead role in one of Nolan's films. This was an opportunity that Murphy had desired and hoped for internally over the course of several years. "I have always said publicly and privately, to Chris [Nolan], 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," Murphy said. "But deep down, secretly, I was desperate to play a lead for him."

Murphy was offered the lead role in 'Oppenheimer' without having to go through the audition process. "He’s so understated and self-deprecating and, in his very English manner, just said, ‘Listen, I’ve written this script, it’s about Oppenheimer. I’d like you to be my Oppenheimer,'" Murphy recalled. "It was a great day."