The story of J. Robert Oppenheimer’s role in the development of the atomic bomb during World War II - Oppenheimer is an upcoming epic biographical thriller film written and directed by Christopher Nolan. It is based on the life of J. Robert Oppenheimer, a theoretical physicist who was pivotal in developing the first nuclear weapons as part of the Manhattan Project and thereby ushering in the Atomic Age. The film stars Cillian Murphy as Oppenheimer, with a supporting cast that includes Emily Blunt, Matt Damon, Robert Downey Jr., Florence Pugh, Josh Hartnett, Casey Affleck, Rami Malek, and Kenneth Branagh. It is Nolan's first film to receive an R rating since Insomnia (2002). According to early reactions, the film is a horrifying and gripping portrayal of the moral dilemmas and personal sacrifices involved in creating the most destructive weapon in history.