Christopher Nolan's upcoming World War II epic Oppenheimer has added yet another actor to its ensemble cast. Vikings-actor Gustaf Skarsgard has boarded the cast of the Universal Pictures film.

The actor joins the previously announced cast including Cillian Murphy, Emily Blunt, Florence Pugh, Robert Downey Jr., Matt Damon, Rami Malek, Benny Safdie, Josh Hartnett, Dane DeHaan, Jack Quaid, Matthew Modine, Dylan Arnold, David Krumholtz, Alden Ehrenreich, Michael Angarano, Louise Lombard, Jason Clarke, David Dastmalchian, Guy Burnet, Josh Peck, and Danny Deferrari.

Revolving around the life of J Robert Oppenheimer, one of the fathers of the atomic bomb, Oppenheimer is an adaptation of Martin Sherwin and Kai Bird's Pulitzer Prize-winning book American Prometheus: The Triumph of J. Robert Oppenheimer

Skarsgard will play Hans Bethe, a German-American nuclear physicist who won the 1967 Nobel Prize in physics and was tasked by Oppenheimer to head up the T (Theoretical) division of the Manhattan Project, the code name for Unites States' programme to develop nuclear weapons during the second world war.

Nolan will write and direct Oppenheimer with Emma Thomas and Charles Rovan co-producing it. Set to hit theatres on July 21, 2023, the film recently began production.