Cillian Murphy Sat Out ‘Oppenheimer’ Cast Dinners on Set Because ‘His Brain Was Just Too Full’: The Pressure on His Shoulders ‘Is So Monumental’

Emily Blunt told People magazine that starring in Christopher Nolans Oppenheimer was like summer camp because the films ensemble cast lived together in New Mexico during production. However, it appears that leading man Cillian Murphy sat out most group activities.

We were all in the same hotel in the middle of the New Mexican desert, Blunt said. We only had each other. Me and Matt [Damon] were roommates and we were like, Lets go to have dinner.'

Murphy did not attend because the sheer volume of what he had to take on and shoulder is so monumental, Blunt added.

Of course he didnt want to come and have dinner with us, Damon said. He couldnt. His brain was just too full.

For Murphy, Oppenheimer marks the biggest leading role of his film career thus far. That kind of pressure isolated the actor. You know that when you have those big roles, that responsibility, you feel its kind of overwhelming, he told People.

NolanandMurphys working relationship spans nearly 20 years and counting as the filmmaker has directed the actor in six movies: Three Batman films, Inception, Dunkirk and Oppenheimer. Notably, the upcoming atomic bomb drama marks Murphys first time headlining a Nolan picture in the lead role. Murphy, who stars as theoretical physicist and father of the atomic bomb J. Robert Oppenheimer, told the Associated Press earlier this year that he was desperate to lead a Nolan movie.

I have always said publicly and privately, to Chris, that if Im available and you want me to be in a movie, Im there. I dont really care about the size of the part, Murphy said. But deep down, secretly, I was desperate to play a lead for him.

Murphy landed the lead role in Oppenheimer via a cold-call offer from Nolan.

Hes so understated and self-deprecating and, in his very English manner, just said, Listen, Ive written this script, its about Oppenheimer. Id like you to be my Oppenheimer, Murphy said. It was a great day We have this long-standing understanding and trust and shorthand and respect. It felt like the right time to take on a bigger responsibility. And it just so happened that it was a huge one.

The all-star cast includes Blunt as Katherine Kitty Oppenheimer, Damon as Manhattan Project director Gen. Leslie Groves Jr. and Robert Downey Jr. as Lewis Strauss, a founding commissioner of the U.S. Atomic Energy Commission. Florence Pugh, Benny Safdie, Michael Angarano, Josh Hartnett, Rami Malek, Dane DeHaan, Dylan Arnold, David Krumholtz, Alden Ehrenreich and Matthew Modine also star.

Oppenheimer opens in theaters July 21 from Universal Pictures.