Oppenheimer is Christopher Nolan's first R rated film since 2002

Christopher Nolan's Oppenheimer has earned a surprise R rating, which means the film will be the director's first R rated effort since 2002's Insomnia.

A new TV spot for the movie confirms the news, revealing that the R rating is down to "some sexuality, nudity, and language." That's a slight surprise, given that, since the film is about the creation of the atomic bomb, violence surely seemed the likelier candidate for an R rating. 

Per The Associated Press, prints for the film – Nolan's longest – also take up a whopping 11 miles of film stock, weighing in at around 600 pounds. Now that sounds like a truly epic movie in every sense of the word. 

"We knew that this had to be the showstopper," Nolan told the publication of the Trinity Test, AKA the first time a nuclear weapon was ever detonated. "We're able to do things with picture now that before we were really only able to do with sound in terms of an oversize impact for the audience – an almost physical sense of response to the film."

The film also involves both black-and-white and color sequences, which Nolan has shed some light upon in conversation with Total Film. "I wrote the script in the first person, which I'd never done before. I don't know if anyone has ever done that, or if that's a thing people do or not… The film is objective and subjective," the director told us in our new issue, which features Oppenheimer on the cover. "The colour scenes are subjective; the black-and-white scenes are objective. I wrote the colour scenes from the first person. So for an actor reading that, in some ways, I think it'd be quite daunting."

Oppenheimer arrives this July 21. In the meantime, check out our guide to all the upcoming major movie release dates for everything else the year has in store.