Christopher Nolan's biographical epic Oppenheimer has gotten its rating, and it'll mark the first time one of his films has received that rating in over two decades.

Variety reported that Oppenheimer is rated R, a first since Insomnia in 2002. Since that film, which was an adaptation of the 1997 Norwegian film of the same name and starred Al Pacino, the late Robin Williams, and Hillary Swank, Nolan has directed the likes of his Batman trilogy, Inception, and Interstellar, and always maintained a PG-13 rating. Heck, even the war epic he did, Dunkirk, was PG-13.

Oppenheimer is shaping up to be Nolan's most ambitious film yet. The Associated Press reported that the prints span 11 miles of film stock and weigh around 600 pounds. They also run through projectors horizontally. Matt Damon also revealed some of the lengths that Nolan went to in order to ensure historical accuracy on the set.

The film tells the story of J. Robert Oppenheimer — the physicist who played a pivotal role in the Manhattan Project and created the atomic bomb. Cillian Murphy stars as the titular physicist and leads an A-list ensemble filled to the brim with talent. Emily Blunt, Matt Damon, Robert Downey Jr., Florence Pugh, Rami Malek, Benny Safdie, Kenneth Branagh, Alden Ehrenreich, Jack Quaid, Josh Peck, Alex Wolf, and even Devon Bostick are in the film. That's not even half of the cast list which is absurd.

Christopher Nolan is coming off the time-bending Tenet. Oppenheimer looks like a much more straightforward film, but Nolan has a knack for making the mundane interesting (just look at Inception). He's a five-time Oscar-nominated director, and perhaps Oppenheimer can be the one that brings him Oscar gold.

Oppenheimer will be released on July 21.