Oppenheimer is a 2023 biographical thriller film written, directed and produced by Christopher Nolan. The film is centered around the life J. Robert Oppenheimer, the American theoretical physicist described as the "father of the atomic bomb" for his role in the Manhattan Project, the World War II undertaking that developed the first nuclear weapons. Based on the 2005 biography American Prometheus by Kai Bird and Martin J. Sherwin, the film chronicles Oppenheimer's studies, his direction of the Los Alamos Laboratory during World War II, and his fall from grace due to his 1954 security hearing, framed between his perspective and that of United States Atomic Energy Commission member Lewis Strauss. The film stars Cillian Murphy as Oppenheimer and Robert Downey Jr. as Strauss, with the ensemble supporting cast including Emily Blunt, Matt Damon, Florence Pugh, Josh Hartnett, Rami Malek, and Kenneth Branagh.
Oppenheimer was announced in September 2021 after Universal Pictures won a bidding war for Nolan's screenplay. It is Nolan's first film not distributed by Warner Bros. Pictures since Memento (2000), due to his conflicts regarding the studio's simultaneous theatrical and HBO Max release schedule. Murphy was the first cast member to sign on the following month, with the rest joining between November 2021 and April 2022. Pre-production began by January 2022, and filming took place from February to May. The cinematographer, Hoyte van Hoytema, filmed Oppenheimer in a combination of IMAX 65 mm and 65 mm large-format film, including, for the first time, scenes in IMAX black-and-white film photography. As with many of his previous films, Nolan used extensive practical effects, with minimal compositing work. Oppenheimer was Nolan's first to receive an R-rating in the United States since Insomnia in 2002.
