Christopher Nolan’s newest project, Oppenheimer, a film based on the book by Kai Bird and Martin J. Sherwin, American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer, already has a star-studded cast that continues to grow. Deadline reported today that Olivia Thirlby has officially joined the cast of the Cillian Murphy-led film.

The film will star Murphy in the titular role of J. Robert Oppenheimer and tell the story of Oppenheimer, The Manhattan Project, and the invention of the atomic bomb. Nolan penned the script and will produce alongside Emma Thomas and Charles Roven.

Thirlby has previously starred in the FX series Y: The Last Man and The L Word: Generation Q, a series from Showtime. She has also appeared in Juno, Dredd, and No Strings Attached.

Oppenheimer is also set to star: Emily Blunt, Robert Downey Jr., Florence Pugh, Matt Damon, Rami Malek, Benny Safdie, Josh Hartnett, Dane DeHaan, Jack Quaid, Matthew Modine, Dylan Arnold, David Krumholz, Alden Ehrenreich, David Dastmalchian, Olli Haaskivi, Jason Clarke, James D’Arcy, Michael Angarano, Guy Burnet, Danny Deferrari, Matthias Schweighöfer, Gary Oldman, Harrison Gilbertson, Emma Dumont, Devon Bostick, Christopher Denham, Trond Fausa, and Josh Zuckerman. Details on any of the roles of this ensemble remain unconfirmed.

Oppenheimer is filming now in New Mexico and will release in theaters on July 21, 2023.