Alex Wolff, who last year appeared in M. Night Shyamalan’s Old and the Nicolas Cage indie hit Pig, is the latest actor to join Oppenheimer, Christopher Nolan’s actor-stuffed biopic on J. Robert Oppenheimer, one of the fathers of the A-bomb.

Cillian Murphy, who appeared in Nolan’s Batman movies as well as the filmmaker’s Dunkirk, is portraying the physicist with the call sheet being more atomically packed than the periodic table of elements: Robert Downey Jr., Matt Damon, Emily Blunt, Florence Pugh, Rami Malek, Benny Safdie, Josh Hartnett, Dane DeHaan, Jack Quaid, Matthew Modine, Alden Ehrenreich, David Krumholtz and David Dastmalchian are among the cast.

The feature has been shooting in New Mexico for a few weeks now and is still adding actors to the mix. Sources say that with Nolan’s secretive process, actors sometimes don’t even know what role they are signing up for until the deal is done. In any case, whether for parts big or small, many in Hollywood are more than eager to parachute in.

Wolff’s role is not being revealed.

The studio has set a July 21, 2023, release date for Oppenheimer, which centers on the theoretical physicist who helped develop the atomic bomb during World War II, but later found his loyalty to the United States questioned by hawkish government officials.

Wolff was one of the stars of Ari Aster’s knuckle-whitening horror movie Hereditary and also appeared in the Jumanji movies.

Wolff, who made his feature directing and writing debut with 2019’s The Cat and the Moon, is repped by WME, Untitled and Definition Entertainment.