Glumci
- Cillian Murphy — J. Robert Oppenheimer
- Matt Damon — Lt. Gen. Leslie Groves
- Emily Blunt — Katherine 'Kitty' Vissering Oppenheimer
- Robert Downey Jr. — Lewis Strauss
- Josh Hartnett — Ernest Lawrence
- Florence Pugh — Jean Tatlock
- Rami Malek — David Hill
- Benny Safdie — Edward Teller
- Jack Quaid — Richard Feynman
- Guy Burnet — George Eltenton
- Danny Deferrari — Enrico Fermi
- Gary Oldman — Harry S. Truman
- Dane DeHaan — Kenneth Nichols
- Matthew Modine — Vannevar Bush
- Dylan Arnold — Frank Oppenheimer
- Alden Ehrenreich — Senate aide
- David Krumholtz — Isidor Isaac Rabi
- Kenneth Branagh — Niels Bohr
- David Dastmalchian — William L. Borden
- Jason Clarke — Roger Robb
- Louise Lombard — Ruth Tolman
- Scott Grimes — Counsel
- Christopher Denham — Klaus Fuchs
- James D'Arcy — Patrick Blackett
- Josh Peck — Kenneth Bainbridge
- Gustaf Skarsgård — Hans Bethe
- Casey Affleck — Boris Pash
- Tom Conti — Albert Einstein
- Matthias Schweighöfer — Werner Heisenberg