Florence Pugh and Cillian Murphy in “Oppenheimer”.Photo:Universal Pictures

Universal Pictures
Christopher Nolanfelt sex scenes were essential for his latest movie.
Thedirector, 52, toldInsiderabout filmingOppenheimerand how he felt about bringing intimate moments between J. Robert Oppenheimer (Cillian Murphy) and Jean Tatlock (Florence Pugh) to the big screen.
Oppenheimeris rated R for “some sexuality, nudity and language.” It’s the first of the director’s movies to include sex scenes; he’s known for films likeThe Dark Knighttrilogy,Inception,Tenet,Dunkirk,Interstellarand more.
“Any time you’re challenging yourself to work in areas you haven’t worked in before, you should be appropriately nervous and appropriately careful and planned and prepared,” Nolan said, asked whether he was nervous how audiences might react to sex scenes in the movie.
Oppenheimerfollows the title character’s involvement with the Manhattan Project during World War II and subsequent interest in nuclear program policy in the years following the war, but it also dives into the physicist’s personal and romantic relationships.
“When you look at Oppenheimer’s life and you look at his story, that aspect of his life, the aspect of his sexuality, his way with women, the charm that he exuded, it’s an essential part of his story,” Nolan said.
Christopher Nolan.Laurent VU/SIPA/Shutterstock

Laurent VU/SIPA/Shutterstock
In both the movie and in real life, Oppenheimer’s relationship with Tatlock proved tricky for his professional and political life in the years following the war. Nolan told Insider that the pair’s affair “had enormous ramifications for [Oppenheimer’s] later life and his ultimate fate” due to Tatlock’s association with the Communist party.
“It felt very important to understand their relationship and to really see inside it and understand what made it tick without being coy or allusive about it, but to try to be intimate, to try and be in there with him and fully understand the relationship that was so important to him,” he said.
Though Nolan’s working relationship withOppenheimer’s star Murphy, 47, dates back to 2005’sBatman Begins, the new movie marked Pugh’s first time working with the director.
Florence Pugh and Cillian Murphy in ‘Oppenheimer’.Melinda Sue Gordon/Universal Pictures

Melinda Sue Gordon/Universal Pictures
Never miss a story — sign up forto stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.PEOPLE’s free daily newsletter.
“I met with her and immediately felt a creative connection,” the director added said of casting Pugh. “I felt this is somebody who could bring Jean Tatlock to life and have the audience understand the significance of this figure in Oppenheimer’s life.”
Nolan and his wife, producer Emma Thomas, attendedOppenheimer’s New York City premiereMonday without Murphy, Pugh or the rest of the film’s cast after Hollywood actorswent on strikelast week.
The movie’s stars, includingMatt Damon,Emily Blunt,Robert Downey Jr.,Rami MalekandJosh Hartnett, walked thered carpetat itsU.K. premiere in Londonlast Thursday but left before the film’s screening as the strike was announced.
Oppenheimeris in theaters Friday.
source: people.com