As reported by Entertainment Weekly, filmmaker Christopher Nolan recently revealed that he scheduled Oppenheimer filming around Cillian Murphy's haircut so the actor wouldn't have to wear a wig. While chatting with The New York Times, Nolan noted that he insisted on working around the star's haircut "because I'm very allergic to wigs in movies."

In Oppenheimer, Murphy stars as theoretical physicist J. Robert Oppenheimer, the man often credited as the creator of the atomic bomb. The upcoming war epic follows Oppenheimer's life from the 1920s to the '60s and shows the alleged "father of the atomic bomb" with a variety of hairstyles.

Nolan told the outlet, "Anytime you get into myriad locations, a lot of different actors, it's always going to be a puzzle."

The Memento director then noted, "I did insist on scheduling it around Cillian's haircut. [Laughs] Because I'm very allergic to wigs in movies. I really wanted the film to not have any obvious artifice when it came to the way characters presented themselves."

RELATED: Christopher Nolan on Why the Time Was Right to Make Oppenheimer

Cillian Murphy Has Worked With Christopher Nolan on a Number of Films, Including Inception and Dunkirk

Florence Pugh and Cillian Murphy in Oppenheimer (2023)
Universal Pictures

Murphy has worked with Nolan on a number of the director's films, starting with 2005's Batman Begins. Since then, the Peaky Blinders star has appeared in other Nolan movies such as Inception, The Dark Knight, The Dark Knight Rises, and Dunkirk.

Still, despite teaming up with the director for multiple films, EW noted that the 28 Days Later star didn't know that Nolan was working on Oppenheimer until the filmmaker reached out to him and asked Murphy if he was interested in playing the title role. During EW's recent Around the Table (which the outlet noted took place prior to the start of the SAG-AFTRA strike that began on July 14th), the A Quiet Place Part II actor admitted that Nolan's preference to reach out unexpectedly could sometimes be "kind of overwhelming."

Murphy told the outlet, "Chris' way of operating is that he just calls you out of the blue. I genuinely had no idea. He said he was making a movie about Oppenheimer and he said, 'I'd like you to play Oppenheimer.' I had to sit down. It was kind of overwhelming."

Similarly, during the chat, the Tenet director stated that his tendency to ring up Murphy at random wasn't without a cost. The Dark Knight Rises director said, "[It's] a fun way to do it, but it means that it's very difficult to call you to go out to dinner or something. Because every time you answer the phone it's like, 'What's it going to be?'"

In addition to Murphy, Oppenheimer also stars Emily Blunt (who plays Oppenheimer's wife, Kitty Oppenheimer), Matt Damon (who plays lieutenant general and U.S. Army Corps of Engineers officer Leslie Groves), Robert Downey Jr. (who tackles the role of Atomic Energy Commission chairman Lewis Strauss), Florence Pugh as Jean Tatlock, Rami Malek as David Hill, Jack Quid as Richard Feynman, and Devon Bostick as Seth Neddermeyer.

Oppenheimer releases in theaters this Friday, July 21st.