Robert Downey Jr. and Matt Damon are closing in on Christopher Nolan’s Oppenheimer

Deadline reports that the two are in talks, while the Hollywood Reporter says they’ve joined. In mid-October it was confirmed that Emily Blunt will star in the Tenet follow-up as well. 

Cillian Murphy, who appeared in a number of Nolan’s previous films—Inception, Dunkirk, and The Dark Knight—has been tapped to play J. Robert Oppenheimer, the physicist known for helming the Manhattan Project, which led to the development of the atomic bomb. The film will be written and directed by Nolan, who is said to be pulling from the 2006 Pultizer Prize-winning book American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer

THR’s sources say Downey will portray Lewis Strauss, “the infamous Atomic Energy Commissioner who initiated hearings that questioned Oppenheimer’s loyalty to the United States and infamously had the scientist’s security revoked.” The outlet hears Damon is playing Lt. Gen. Leslie Groves, the Manhattan Project’s director.

Oppenheimer will mark Nolan’s first film with Universal following his harsh criticism toward longtime collaborator Warner Bros. over the studio’s choice to make every film on its 2021 schedule premiere simultaneously in theaters and on its streaming service HBO Max. “Some of our industry’s biggest filmmakers and most important movie stars went to bed the night before thinking they were working for the greatest movie studio and woke up to find out they were working for the worst streaming service,” Nolan said in a statement. 

The 51-year-old’s criticism came after Tenet was pushed through in the height of the COVID-19 pandemic, and underperformed at the box office, making less than $400 million worldwide and just over $58 million domestically. The film’s budget was a reported $200 million, and doesn’t take marketing costs into account. Variety reported Warner Bros. could lose an estimated $100 million, while insiders at the studio painted a rosier picture of about $50 million. 

As part of his deal with Universal, Nolan will receive a 100-day theatrical window for Oppenheimer, and a “blackout period where the studio would not release another movie for three weeks before and after the feature.”