Oppenheimer: Robert Downey Jr, Matt Damon join cast of Christopher Nolan’s next

Robert Downey Jr and Matt Damon will join Christopher Nolan’s next project, Oppenheimer.

Hollywood superstars Robert Downey Jr and Matt Damon joined the cast of Christopher Nolan's upcoming directorial Oppenheimer.

Robert Downey Jr and Matt Damon to join Christopher Nolan’s film, Oppenheimer.

According to a report by The Hollywood Reporter, the two actors are joining previously announced cast members Cillian Murphy and Emily Blunt in the film. The Universal Pictures project is a biopic of J Robert Oppenheimer, the theoretical physicist remembered as one of the fathers of the atom bomb.

Oppenheimer will be the first time that Robert, the star of many Marvel Cinematic Universe (MCU) movies, and Oscar winner Matt will work with Christopher. The details of their roles have been kept under wraps.

Cillian is set to star as J Robert Oppenheimer and Emily Blunt as his wife Katherine. Cillian and the director have worked on three films previously –Batman Begins, Inception and Dunkirk.

Oppenheimer is based on the Pulitzer Prize-winning book American Prometheus: The Triumph and Tragedy of J Robert Oppenheimer by Kai Bird and Martin J Sherwin. Christopher will write and direct the film, while his creative partner and wife Emma Thomas, will produce with Charles Roven of Atlas Entertainment.

The studio has described the film as an "epic thriller that thrusts audiences into the pulse-pounding paradox of the enigmatic man who must risk destroying the world in order to save it". Christopher's last film was Tenet, the 2020 globetrotting espionage film starring John David Washington, Robert Pattinson, Kenneth Branagh and Elizabeth Debicki, among others.

Oppenheimer is slated to be released in theatres on July 21, 2023.

Robert was last seen in Dr Dolittle and will be seen reprising his role as Sherlock Holmes for the upcoming sequel in the franchise. Matt was last seen in the 2019 action biographical drama Ford v Ferrari. He will also be seen in Marvel's 2022 film, Thor: Love and Thunder.