Cillian Murphy and Robert Downey Jr. have been spotted looking dapper in period-appropriate attire on the set of Christopher Nolan's Oppenheimer.

Oppenheimer is becoming one of the most highly anticipated films over the next year as Christopher Nolan makes an exciting return to the big screen. The premise follows the American physicist J. Robert Oppenheimer, the father of the atomic bomb, created under the Manhattan Project. Cillian Murphy is set to play Oppenheimer, and Robert Downey Jr. will portray Atomic Energy Commission chairman Lewis Strauss. Emily Blunt, Florence Pugh, Matt Damon, Gary Oldman, Kenneth Branagh, and Rami Malek are also joining the film, with a projected release date of July 21, 2023.

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Cillian Murphy is no stranger to period clothing due to his role as Thomas Shelby in Peaky Blinders. Many would agree he manages to make suspenders and fedoras look good. On the set of Oppenheimer located in New Jersey, Murphy was spotted wearing a brown overcoat, a white dress shirt, brown suspenders, and brown pants with a brown fedora donned in other scenes. For the role of Strauss, Downey has been seen to sport a white, thinning hairstyle, which accompanies his light blue/ grey suit with braces, a white shirt, and a blue tie. The Sherlock Holmes actor is also seen wearing a pair of round, black glasses, looking as if he stepped right out of the 1940s. The two have been seen chatting to each other and enjoying themselves on set.

Nolan's latest project will be an adapted version of the 2006 book American Prometheus: The Triumph and Tragedy of Oppenheimer by Kai Bird and the late Martin J. Sherwin. The story marks Oppenheimer's life from his development of the atomic bomb and his conflicts with Strauss throughout the historic bombings of Hiroshima and Nagasaki. It seems likely that the film will depict a rivalry between the two men; however, due to the secrecy around filming, movie-goers can only speculate.

Due to its secrecy, fans will have to do with set photos for now as the expected release date is a long way away. Universal has described Oppenheimer as an epic thriller that "thrusts audiences into the pulse-pounding paradox of the enigmatic man who must risk destroying the world to save it." And with such an incredible cast where the names stack up, combined with the genius of Nolan, the film is shaping up to be very promising.

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Source: Letterboxd/ Twitter.