'Oppenheimer' Cast: Meet the A-List Actors Starring in the Christopher Nolan Film

As one of the year's most highly-anticipated films, Christopher Nolan’s Oppenheimer almost needs no introduction.

Based on the biography American Prometheus about J. Robert Oppenheimer, the theoretical physicist who developed the first nuclear weapons during World War II, the epic drama explores his life and his work.

Peaky Blinders’ Cillian Murphy plays the titular character, but he’s just one name in the star-studded cast. Alongside young actors like Florence Pugh, Dylan Arnold and Jack Quaid are icons like Robert Downey Jr., Emily Blunt and Matt Damon.

In fact, Downey Jr. described Oppenheimer as the “best film I’ve ever been in” at the London premiere on July 13, adding, “I cannot wait for you all to experience it."

“This is what a summer blockbuster, when I was growing up, used to be," he continued. "It just kind of, like, changed your life. But again, you know, it’s why Chris Nolan is who he is.”

From their past roles to personal lives, here's everything to know about the cast of Oppenheimer.

Cillian Murphy as J. Robert Oppenheimer

Murphy, 47, plays the titular character, Robert J. Oppenheimer. The Irish actor is best known for his starring role as Tommy Shelby in the BBC drama Peaky Blinders. In 2020, he also had a role in the horror sequel A Quiet Place Part II.

He married visual artist Yvonne McGuinness in 2004 after they met in the '90s, and they lived in London for 14 years before moving to Dublin in 2015. They have two sons, Malachy (born in 2005) and Aran (born in 2007).

Emily Blunt as Katherine “Kitty” Oppenheimer

Blunt, 40, plays Katherine “Kitty” Oppenheimer, the wife of Murphy’s character. Like her on-screen husband, she had a main role in the A Quiet Place series. Blunt is also known for movies like The Devil Wears Prada, Salmon Fishing in the Yemen, Mary Poppins Returns and The Girl on the Train.

The London-born actress has been married to The Office star John Krasinski since 2010. The couple have two daughters, Hazel (born in 2014) and Violet (born in 2016).

Matt Damon as Lieutenant General Leslie Groves

Damon, 52, plays U.S. military officer Leslie Groves. Damon has starred in Good Will Hunting, The Talented Mr. Ripley, Saving Private Ryan and Mars, and he also played the titular character in the Bourne franchise.

He married Luciana Barroso in 2005 after they met while he was filming Stuck on You in 2003. Together, they have four daughters: Isabella, Gia, Stella and Alexia, who is Barroso's daughter from a previous relationship.

Robert Downey Jr. as Lewis Strauss

Robert Downey Jr., 58, plays Lewis Strauss, chairman of the U.S. Atomic Energy Commission (AEC) and adversary of Oppenheimer. As Hollywood’s highest-paid actor from 2013 to 2015, per Variety, he might be best known for playing Iron Man in the Marvel Cinematic Universe (MCU). He also portrayed Sherlock Holmes in the Guy Ritchie movie of the same name.

Downey married Susan Downey (née Levin) in 2005, and they have two kids: a son, Exton, born in 2012, and a daughter, Avri, born in 2014. Downey Jr. was previously married to actress and singer Deborah Falconer from 1992 to 2004 — they have a son, Indio, born in 1993.

Florence Pugh as Jean Tatlock

Pugh, 27, plays psychiatrist Jean Tatlock, who had a relationship with the movie’s titular character. She rose to fame in 2019 after playing Dani in Midsommar and Amy March in Little Women. She also had roles in Don’t Worry Darling (alongside Harry Styles) and The Wonder and starred as Yelena Belova in the MCU movie Black Widow.

Born in the British city of Oxford, one of her siblings is Game of Thrones actor Toby Sebastian. She lived in Spain for three years as a child, as her family hoped the warmer weather there would be good for her health — she had tracheomalacia as a child. From 2019 to 2022, Pugh was in a relationship with fellow actor Zach Braff after meeting while working on a short film.

Josh Hartnett as Ernest Lawrence

Hartnett, 44, plays nuclear physicist Ernest Lawrence. He’s known for his starring roles in war films Pearl Harbor and Black Hawk Down, as well as the rom-com 40 Days and 40 Nights and the drama O. From 2014 to 2016, he played Ethan Chandler in the Showtime horror series Penny Dreadful.

He’s been in a relationship with English actress Tamsin Egerton since 2012, and the couple have three children. He married Egerton in 2021.

Casey Affleck as Boris Pash

Affleck, 47, plays military intelligence officer Boris Pash. The younger brother of Ben Affleck began his career as a child actor in the 1980s and rose to prominence in 2007 after he played outlaw Robert Ford in The Assassination of Jesse James by the Coward Robert Ford and appeared in Gone Baby Gone, his brother’s directorial debut.

He married Summer Phoenix in 2006 after they dated for six years; her brother, Joaquin, introduced them. Affleck and Phoenix had two sons together, born in 2004 and 2007. However, Phoenix filed for divorce in August 2017, and their divorce was finalized later that year. Since 2021, Affleck has been in a relationship with Caylee Cowan.

Rami Malek as David Hill

Rami Malek, 42, plays experimental physicist David Hill. Malek was born in California to Egyptian parents and is best known for his Emmy-winning role as computer hacker Elliot Alderson in USA Network’s Mr. Robot (2015 to 2019). In 2018, he notably portrayed Freddie Mercury in the 2018 biopic Bohemian Rhapsody, for which he won an Oscar, a Golden Globe and a SAG award.

Malek lives a private life but has been in a relationship with his Bohemian Rhapsody costar Lucy Boynton since 2018.

Kenneth Branagh as Niels Bohr

Kenneth Branagh, 62, plays Danish physicist Niels Bohr. The Northern Irish Branagh has directed and starred in many Shakespeare adaptations over the years and was knighted in 2012 for his work in film, according to BBC. In 2002, he won an Emmy for his role as Reinhard Heydrich in the HBO movie Conspiracy.

In 2003, Branagh married film art director Lindsay Brunnock, whom he met while shooting Shackleton the year prior. He was previously married to Emma Thompson, though they split in 1995 following his affair with Helena Bonham Carter.

Benny Safdie as Edward Teller

Safdie, 37, plays theoretical physicist and “father of the hydrogen bomb” Edward Teller. He’s perhaps best known for working with his brother Josh on movies like 2017’s Good Time and 2019’s Uncut Gems. Safdie has also starred in Licorice Pizza, Person to Person and Pieces of a Woman.

Benny is married to Ava Safdie, and they have two children together.

Dylan Arnold as Frank Oppenheimer

Arnold, 29, plays Frank Oppenheimer, the titular character’s younger brother. He’s known for playing Noah in the 2019 romantic drama After and its sequel and Cameron Elam in the 2018 slasher Halloween and its sequel. However, he might be best known for the role of Theo Engler in the third season of Netflix’s You.

In 2021, Arnold and his You costar Victoria Pedretti sparked dating rumors when they were spotted running errands together in Los Angeles.

Gustaf Skarsgård as Hans Bethe

Gustaf Skarsgård, 42, plays theoretical physicist Hans Bethe. The Swedish actor, brother to fellow stars Alexander, Bill and Valter, is known for roles in movies like The Way Back and Kon-Tiki, and for playing Floki in the History Channel’s Vikings from 2013 to 2020. He’s also had roles in HBO TV’s Westworld and Netflix’s Cursed.

Skarsgård is in a relationship with Caroline Sjöström. Their daughter was born in November 2020.

David Krumholtz as Isidor Rabi

David Krumholtz, 45, plays physicist and Nobel Prize winner Isidor Rabi. The actor has had a number of TV and film roles over the years, appearing in Joss Whedon’s 2005 space western Serenity, the CBS crime drama Numb3rs and The Santa Clause franchise.

In 2010, he married actress Vanessa Britting after a two-year engagement. They have a daughter and a son born in 2014 and 2016, respectively. In 2011, Krumholtz was diagnosed with thyroid cancer. In May 2021, he celebrated 10 years cancer-free.

Matthew Modine as Vannevar Bush

Matthew Modine, 64, plays Vannevar Bush, the head of the U.S. Office of Scientific Research and Development during World War II. His breakout role was as J.T. “Joker” Davis in the 1987 war drama Full Metal Jacket. In recent years, he’s perhaps more noted for playing Dr. Martin Brenner in Netflix’s Stranger Things.

In 1980, Modine married Caridad Rivera. Their son, assistant film director Boman, was born in 1985, and their daughter, actress, dancer and singer Ruby, was born in 1990. She’s perhaps best known for playing Sierra Morton in Shameless.

Emma Dumont as Jackie Oppenheimer

Emma Dumont, 28, plays Jackie Oppenheimer, J. Robert Oppenheimer's sister-in-law. The Seattle-born Dumont is best known for her roles in the ABC Family comedy-drama Bunheads, NBC’s period crime drama Aquarius and FOX’s superhero series The Gifted.

She’s relatively private, but as a teenager, Dumont was a big roller derby skater and used to take part in robotics challenges. She began doing ballet at age 3 and performing in community theater at age 6.

Jack Quaid as Richard Feynman

Jack Quaid, 31, plays theoretical physicist Richard Feynman. He began his acting career in his late teens playing Marvel in The Hunger Games, before his main role in the HBO period drama series Vinyl and then the starring role of Hughie Campbell in the Amazon Prime superhero series The Boys. He’s also appeared in 2022's Scream and Scream VI.

Born to Meg Ryan and Dennis Quaid, Quaid comes from a family of actors. From 2016 to 2021, he was linked to actress Lizzy McGroder. He has been most recently linked to his The Boys costar Claudia Doumit.

Gary Oldman as Harry S. Truman

Gary Oldman, 65, plays President Harry S. The London-born actor has been one of the biggest names in Hollywood for over three decades. In recent years, he’s become known for playing Winston Churchill in Darkest Hour, George Smiley in Tinker Tailor Soldier Spy, and Sirius Black in the Harry Potter franchise.

He’s been married five times: to Lesley Manville, Uma Thurman, Donya Fiorentino, Alexandra Edenborough and Gisele Schmidt — whom he married in 2017. He has a son with Manville, born in 1988, and two sons with Fiorentino, born in 1997 and 1999.

Olivia Thirlby as Lilli Hornig

Olivia Thirlby, 36, plays scientist Lilli Hornig. She began her career in 2006 with roles in NBC’s crime drama Kidnapped and the thriller United 93 and rose to prominence a year later with a role in Juno. She’s also featured in sci-fi action movies The Darkest Hour and Dredd.

While filming Juno, she was in a relationship with costar Elliot Page, and in 2014, she married Dredd costar Jacques Pienaar.

Tom Conti as Albert Einstein

Tom Conti, 81, plays legendary scientist Albert Einstein. The Scottish actor has taken on a wide range of roles throughout his career, winning a Tony Award in 1979 for his role in Whose Life Is It Anyway? and starring in the likes of Reuben, Reuben (for which he was nominated for an Oscar) and The Dark Knight Rises.

He has been married to actress Kara Wilson since 1967, and they have a daughter, Nina Conti, a comedian and ventriloquist.

Dane DeHaan as Kenneth Nichols

Dane DeHaan, 37, plays army officer Kenneth Nichols. He began his acting career in 2008 as an understudy to Haley Joel Osment in Broadway’s American Buffalo before landing a role in an episode of Law & Order: Special Victims Unit. Since then, he’s appeared in the 2012 superhero thriller Chronicle, the 2013 drama Kill Your Darlings and the 2014 MCU film The Amazing Spider-Man 2.

He married actress Anna Wood in 2012. The pair first met in high school in North Carolina, where he transferred for his senior year, and they also appeared in Chronicle together. They have two children together.

Josh Peck as Kenneth Bainbridge

Josh Peck, 36, plays physicist Kenneth Bainbridge. The N.Y.C.-born actor rose to prominence as a child actor on Nickelodeon, first on The Amanda Show and then as Josh Nichols alongside Drake Bell in Drake & Josh. In recent years, he’s appeared alongside John Stamos in the FOX sitcom Grandfathered and has starred in Hulu’s How I Met Your Father.

Peck married Paige O’Brien in June 2017, and the couple have two children together. Their elder son, Max, was born in December 2018, and their younger son, Shai, arrived in October 2022.

Alex Wolff as Luis Walter Alvarez

Alex Wolff, 25, plays experimental physicist Luis Walter Alvarez. Like Peck, he rose to fame on Nickelodeon, appearing alongside his brother Nat in The Naked Brothers Band, which his mother Polly Draper created. The brothers then formed a band, Nat & Alex Wolff, and starred in their mom’s 2018 comedy-drama Stella’s Last Weekend.

Wolff's mom, Polly, is an actress and writer, while his father is jazz pianist Michael Wolff.

Tony Goldwyn as Gordon Gray

Tony Goldwyn, 63, plays the attorney and government official Gordon Gray. From 2012 to 2018, he played President Fitzgerald Grant III in the ABC drama Scandal and won a Peabody Award.

He’s been married to Jane Musky since 1987, and the couple have two daughters, Anna and Tess.