One of the most talked-about elements of Christopher Nolan’s ambitious biopic Oppenheimer is its star-studded cast, with each of the actors playing a real-life character. Set during the height of the Second World War, Oppenheimer recreates the events that led to the creation of the first atomic bomb and its tumultuous aftermath. While Cillian Murphy leads the pack as the titular scientist, the visually spectacular epic involves many multi-faceted characters. J. Robert Oppenheimer’s peers and legendary scientists like Albert Einstein make it to the ensemble, along with some of the closest people in his life, such as his wife Katherine Oppenheimer and former romantic partner Jean Tatlock.
The Oppenheimer true story is incomplete without the Manhattan Project, the secretive American military project that involved the creation of a whole new settlement while testing out the atomic bomb. So, naturally, many actual military figures associated with the Project also get their fair share of screen time in Oppenheimer. But considering its three-hour-runtime and grand historical scale, Oppenheimer doesn’t limit its namesake’s life to just his scientific creations. A major chunk of the narrative also dabbles in Oppenheimer’s legal troubles because of his political affiliations. Hence, the Oppenheimer character ensemble becomes complete with the addition of legal and bureaucratic players.
Cillian Murphy As J. Robert Oppenheimer
The Oppenheimer cast is steered by Cillian Murphy, who plays the titular protagonist, a gifted American scientist who his government calls upon to devise the most destructive weapon known to humankind. Facing mental dilemmas of his own, Oppenheimer took anti-war stances after the bomb and was even put on trial for his political associations. Murphy previously collaborated with Christopher Nolan to play the deranged pharmacologist Dr. Jonathan Crane a.k.a. Scarecrow in The Dark Knight trilogy, the emotionally inept business empire heir Robert Fischer in Inception and an unnamed shell-shocked soldier in Dunkirk. Murphy is also known for playing the chivalrous gangster Thomas Shelby in Peaky Blinders.
Emily Blunt As Katherine “Kitty” Oppenheimer
Emily Blunt supports Cillian Murphy as Oppenheimer’s wife, Kitty. However, the real Kitty stands out on her own as a biologist, botanist and a member of the Communist Party (a political alignment that put her in danger during the era of McCarthyism). She stayed with Oppenheimer for over two decades until his death in 1967. Blunt has previously dabbled in the biopic genre with roles like Queen Catherine Howard in the miniseries Henry VIII and Queen Victoria in The Young Victoria. She is also known for her stint as the survivalist mother, Evelyn Abbott, in A Quiet Place movies, the second of which also featured Cillian Murphy.
Matt Damon As Leslie Groves
The United States Army officer who served as the primary director of Projector Manhattan is the one who convinced Oppenheimer to get involved in the top-secret operation. Groves was convinced that Oppenheimer’s work would help reduce the Second World War’s duration and bring American soldiers back home. The decorated veteran is played by Matt Damon, who is no stranger to playing real-life figures on screen. The Oscar winner previously played race car driver-turned-automobile designer Carroll Shelby in Ford v Ferrari, South African rugby player François Pienaar in Invictus, medieval French knight Jean de Carrouges in The Last Duel and Nike marketing executive Sonny Vaccaro in Air.
Robert Downey Jr. As Lewis Strauss
Oppenheimer switches between color and monochrome formats, with the black-and-white scenes focusing on the security hearing conducted by the United States Atomic Energy Commission. This prestigious body was once headed by Robert Downey Jr’s Oppenheimer character Lewis Strauss, who revoked Oppenheimer’s security clearance. It’s for this decision that he’s usually seen as a villainous figure in American history. Downey previously dabbled in the biopic genre as slapstick legend Charlie Chaplin in the biopic Chaplin. He is otherwise popularly known for his lead roles as the armored Avenger Iron Man in the Marvel Cinematic Universe and the Victorian-era detective Sherlock Holmes in the titular franchise.
Florence Pugh As Jean Tatlock
A psychiatrist and member of the Communist Party, Jean Tatlock is the other major woman with whom Oppenheimer was romantically associated. The age gap between the two personalities has not exactly aged well, considering Jean was a student, and Oppenheimer was her professor when they began seeing each other. Florence Pugh joins the Oppenheimer cast to play the tragic figure. The Oscar nominee has played similarly broken and turbulent characters in the past, such as the youngest March sibling Amy in Little Women and grieving psychology student Dani in Midsommar. She is also associated with the Marvel Cinematic Universe as the highly-trained spy and assassin Yelena Belova.
Josh Hartnett As Ernest Lawrence
Nobel Prize winner and the inventor of the cyclotron, physicist Ernest Lawrence and Oppenheimer’s friendship dates back to their days as researchers at Berkeley. When it comes to the Manhattan Project, Lawrence was mainly involved in the process of extracting enriched uranium. The Oppenheimer cast expands upon its star power with Josh Hartnett playing the part. While Hartnett plays a wartime scientist this time, he previously played soldiers like Pearl Harbor’s World War II combat pilot Danny Walker and Black Hawk Down’s Matthew Eversmann, a U.S. Army Staff Sergeant stationed in combat-struck Somalia. His period roles also include the charming sharpshooter Ethan Chandler in the horror drama series Penny Dreadful.
Casey Affleck As Boris Pash
Casey Affleck stars in Oppenheimer as U.S. military intelligence officer Boris Pash who notably commanded the Alsos Mission. This American-British military operation sought to detect enemy scientific developments during the Second World War. While Oppenheimer marks Affleck’s first collaboration with Christopher Nolan, he frequently appeared alongside his fellow cast member Matt Damon in movies like the Ocean’s trilogy, Good Will Hunting and Interstellar. Manchester By The Sea won Casey Affleck an Oscar for his performance as depressed janitor Lee Chandler. His other prominent roles include American outlaw Robert Ford in The Assassination of Jesse James by the Coward Robert Ford and dutiful private investigator Patrick Kenzie in Gone Baby Gone.
Rami Malek As David Hill
David Hill was one of the physicists who accompanied Oppenheimer at the Los Alamos Laboratory, even though not much is known about him compared to the movie’s other real-life figures. The character is portrayed by Rami Malek, a prominent face in the biopic genre, given his Oscar-winning turn as the late Queen frontman Freddie Mercury in Bohemian Rhapsody. Malek also earned an Emmy for playing the paranoid computer hacker Elliot Alderson in Mr. Robot. He joined the James Bond franchise as the vengeance-seeking Bond villain Lyutsifer Safin in No Time To Die. He also starred in the Night at the Museum trilogy as ancient Egyptian Pharaoh Ahkmenrah.
Kenneth Branagh As Niels Bohr
Niels Bohr is one of the most celebrated modern scientists, thanks to his Nobel Prize-winning contributions to understanding atomic structure and quantum theory. Oppenheimer held the Danish physicist in high regard, and as Nolan’s movie suggests, Bohr was also an occasional mentor to the American. Bohr is played in the movie by frequent Nolan collaborator Kenneth Branagh who previously played the antagonistic Russian oligarch Andrei Sator in Tenet and the heroic naval Commander Bolton in Dunkirk. The Oscar-winning director and screenwriter also played other real-life figures like actor Laurence Olivier in My Week With Marilyn and American President Franklin D. Roosevelt in Warm Springs.
Oppenheimer Supporting Cast & Characters
Benny Safdie as Edward Teller: Benny Safdie joins the Oppenheimer cast as Hungarian-American physicist Edward Teller who is widely regarded as the “father of the Hydrogen bomb.” Safdie is an accomplished director with his brother Josh Safdie, collectively directing Good Time and Uncut Gems. He also played Robert Pattinson’s on-screen brother Nick Nikas in Good Time.
Dylan Arnold as Frank Oppenheimer: American particle physicist Frank Oppenheimer was J. Robert Oppenheimer’s younger brother. Before playing his part in Oppenheimer, Dylan Arnold appeared in college student Theo Engler in You season 3 and troubled teenager Cameron Elam in 2018’s Halloween and its sequel Halloween Kills.
Gustaf Skarsgård as Hans Bethe: The Oppenheimer character ensemble has no shortage of Nobel laureates, with Hans Bethe being one of them. The German-American theoretical physicist was head of the Theoretical Division at the Los Alamos laboratory. He is played by Gustaf Skarsgård, known for playing the wizard Merlin in Cursed and the shipbuilder Floki in Vikings.
David Krumholtz as Isidor Isaac Rabi: The physicist Isidor Isaac Rabi was a longtime friend of Oppenheimer’s but refused to work with him on Manhattan Project. He is played by David Krumholtz, who portrayed the mathematical genius Charlie Eppes in Numb3rs and the reclusive hacker Mr. Universe in Serenity.
Matthew Modine as Vannevar Bush: Vannevar Bush was not just a gifted engineer and scientist but also a science administrator, looking over the initiation of Manhattan Project. He is played by Matthew Modine, who also appeared in Full Metal Jacket as disillusioned Vietnam War soldier Private Joker and in Stranger Things as the villainous scientist Dr. Martin Brenner.
David Dastmalchian as William L. Borden: An American lawyer who ardently accused Oppenheimer of being a Soviet agent, William L Borden was one of Oppenheimer’s staunchest critics. He is played by David Dastmalchian who previously collaborated with Nolan as one of the Joker’s minions Thomas Schiff in The Dark Knight. Dastmalchian also has an incredible superhero record appearing in numerous comic book properties, such as playing the Polka-Dot Man in The Suicide Squad and the magician Abra Kadabara in the Flash series.
Michael Angarano as Robert Serber: Robert Serber was one of the many physicists who were involved in the Manhattan Project. He is played by Michael Angarano, who broke out in Sky High in which he played the superhero freshman William “Will” Theodore Stronghold. He also starred alongside martial arts legends Jackie Chan and Jet Li in The Forbidden Kingdom as high-schooler and kung fu cinema aficionado Jason Tripitikas.
Jack Quaid as Richard Feynman: The Oppenheimer cast also includes The Boys star Jack Quaid, who plays theoretical physicist Richard Feynman. The charming scientist was also a public figure following his involvement in Los Alamos. He is portrayed by Jack Quaid, who stars in The Boys as the mild-mannered vigilante Hughie Campbell, and voices Superman in My Adventures with Superman.
Tom Conti as Albert Einstein: The legendary physicist Albert Einstein held diverging views from Oppenheimer when it came to atomic weapons, but the two continue to hold a close friendship. Tom Conti plays Einstein in Oppenheimer. The Scottish theater veteran was nominated for an Oscar for his portrayal of a writers’ block-struck poet Gowan McLand in Reuben, Reuben.
Josh Peck as Kenneth Bainbridge: The Director of Manhattan Project’s monumental Trinity nuclear test (that led to the first-ever detonation of a nuclear weapon), Kenneth Bainbridge is played by Josh Peck, who is best known for playing the diligent school student Josh Nichols in Drake and Josh.
Olivia Thirlby as Lilli Hornig: Feminist activist and Manhattan Project scientist Lilli Hornig also appears in Oppenheimer, played by Olivia Thirlby. She previously played the titular protagonist’s friend Leah in Juno and dystopian law enforcer Judge Anderson in Dredd.
Dane DeHaan as Kenneth Nichols: Kenneth Nichols was a civil engineer who also worked on the Manhattan Project and played a key role in the legal proceedings against Oppenheimer. He is played by Dane DeHaan, who has played morally gray characters like the supervillain Green Goblin/Harry Osborn in The Amazing Spider-Man 2 and the superpowered teen Andrew Detmer in Chronicle.
Danny Deferrari as Enrico Fermi: As Oppenheimer features the greatest nuclear scientists, it’s not surprising that even Enrico Fermi makes an appearance. The Italian-American scientist is largely attributed behind the world’s first nuclear reactor. He is portrayed by Danny Deferrari, who previously starred in Shiva Baby as the protagonist’s sugar daddy Max.
Alden Ehrenreich as a Senate aide: One of the aides to the Senate Committee trying Oppenheimer is played by Alden Ehrenreich, who is otherwise known for starring in Solo as a younger version of the Star Wars space bounty hunter Han Solo.
Jefferson Hall as Haakon Chevalier: Haakon Chevalier befriended Oppenheimer during their academic tenures at Berkeley. But unlike Oppenheimer’s other peers, Chevalier was not a scientist but a writer and French literature professor. Jefferson Hall joins the Oppenheimer cast to play the academic. Jefferson Hall is unique for appearing in both Game of Thrones and its spin-off House of the Dragon. He portrayed the Lannister twins in House of the Dragon, preceded by a brief role as the knight Hugh of Vale in Game of Thrones.
Jason Clarke as Roger Robb: The special counsel to Oppenheimer’s hearing, Jason Clarke plays Roger Robb. The New Zealand native played the Resistance leader-turned-Terminator John Connor in Terminator Genisys and American astronaut Ed White in First Man.
James D’Arcy as Patrick Blackett: British experimental physicist Patrick Blackett was one of Oppenheimer’s early advisers. He is played by James D’Arcy, who previously collaborated with Nolan in Dunkirk as World War II-era soldier Colonel Winnant.
Tony Goldwyn as Gordon Gray: Government official Gordon Gray chaired a committee that recommended revoking Oppenheimer’s security clearance in the 1950s. The controversial lawmaker is played by Tony Goldwyn, who appeared as Richard Nixon’s brother Harold in the biopic Nixon and the astronaut Neil Armstrong in the miniseries From the Earth to the Moon.
Devon Bostick as Seth Neddermeyer: Seth Neddermeyer was a visionary in nuclear physics, given his emphasis on implosion-type nuclear bombs while working on Manhattan Project. The scientist is played by Devon Bostick, who played the bullying elder brother Rodrick in the first three Diary of a Wimpy Kid movies and the post-apocalyptic juvenile delinquent Jasper in The 100.
Alex Wolff as Luis Walter Alvarez: Experimental physicist Luis Alvarez was involved in the Manhattan Project to design explosive lenses. Before his stint on the Oppenheimer cast as Alvarez, Alex Wolff starred in Hereditary as the traumatized 16-year-old Peter Graham.
Josh Zuckerman as Giovanni Rossi Lomanitz: A protege of Oppenheimer’s from his time at Berkeley, Giovanni Rossi Lomanitz was one of the many physicists involved in the Manhattan Project. Josh Zuckerman’s roles include the titular protagonist in the animated series, It’s Pony, and the series lead Naomi Clark’s love interest Max Miller in 90210.
Matthias Schweighöfer as Werner Heisenberg: A pioneering name in quantum physics, Nobel Prize winner Werner Heisenberg is played by Matthias Schweighöfer. The German actor and filmmaker is known for playing mastermind thief Ludwig Dieter in Army of the Dead and its prequel Army of Thieves.
Emma Dumont as Jackie Oppenheimer: Oppenheimer’s sister-in-law and an active member of the Young Communist League, Jackie Oppenheimer, is played by Emma Dumont. The American actress-model-dancer is best known for playing the magnetism-controlling mutant Polaris in the X-Men spin-off The Gifted.
Christopher Denham as Klaus Fuch: German theoretical physicist, Klaus Fuch, was a Soviet spy who supplied crucial information on the Manhattan Project to the Soviet Union after the Second World War. He is played by Christopher Denham, who appeared in Argo as real-life U.S. diplomat Mark Lijek.
David Rysdahl as Donald Hornig: One of the men behind the preparation of the Manhattan Project’s Trinity Test, Donald Horning, is portrayed by David Rysdahl. He previously starred in Nine Days as Mike, a man trapped in a purgatory-like realm, and in No Exit as kidnapping suspect Lars.
Gary Oldman as Harry S. Truman: The American President Harry S. Truman took over presidential duties from Franklin D. Roosevelt after the Second World War and continued his term during Oppenheimer’s trials. The crucial political figure is played by Gary Oldman, who reunites with Nolan after playing the committed police officer Jim Gordon in his Dark Knight trilogy. The Oppenheimer cast member has dabbled in similar biographical roles before winning an Oscar for playing UK Prime Minister Winston Churchill in Darkest Hour.