Matt Damon's Oppenheimer Character Explained (& What The Actor's Said About His Role)

Matt Damon's appearance in Oppenheimer as Lt. General Leslie Groves is as memorable as any in the celebrated historical epic. The cast of Oppenheimer is filled with some of the biggest heavy-weight actors playing some of the most important people in recent American history. It's a bit darkly humorous that it took an Englishman like Christopher Nolan to thoroughly examine one of the most defining moments of the United States. Dozens of real critical figures are accounted for in Oppenheimer, some for a scene, others as main characters.

After a brief but critical role in Interstellar, Matt Damon finally got a starring part in a Nolan production. Damon's career really does not need much introduction. He's been headlining movies for the greatest working directors since his debut in Donald Petrie's Mystic Pizza. There's never really been a down year for him. While he's succeeded in playing every type of character, some of his best work comes when he's playing an unlikeable character. He can channel anxiety and rage very well, and his role in Oppenheimer lets him combine that character with his knack for playing imposing, capable figures.

Matt Damon Plays Lt. General Leslie Groves In Oppenheimer

Groves Was An Officer In The United States Army Corps Of Engineers

Close

Matt Damon co-stars in Oppenheimer as Lt. General Leslie Groves, a real-life United States Army Corps of Engineers officer. Born on August 17, 1896, Groves quickly learned the ways of the military thanks to his father, Leslie Richard Groves Sr., a Presbyterian chaplain in the Army, and Groves Jr. spent his early life moving from Army post to Army post (via TheNMUSA). After graduating from West Point, he was assigned to the U.S. Army Corps of Engineers as a 2nd lieutenant and spent his early career working on construction projects around the nation.

After his successful work on building the Pentagon, mentioned in Oppenheimer, Groves was selected to head the then-secret Manhattan Project. Groves had a reputation for having a big ego, and it's notable that in Oppenheimer, he calls out Robert (Cillian Murphy) for his. Perhaps it takes one to know one. Those who knew Groves said (via AHF),

"First, General Groves is the biggest S.O.B. I have ever worked for. He is most demanding. He is most critical. He is always a driver, never a praiser. He is abrasive and sarcastic. He disregards all normal organizational channels. He is extremely intelligent. He has the guts to make timely, difficult decisions. He is the most egotistical man I know. He knows he is right and so sticks by his decision. He abounds with energy and expects everyone to work as hard, or even harder, than he does… if I had to do my part of the atomic bomb project over again and had the privilege of picking my boss, I would pick General Groves."

Damon plays this crusty, hard-edged, but incredibly capable figure extremely well. He perfectly portrays why Groves could be hard to deal with but also why he was the right man for the job, and why he and Oppenheimer got on so well, at least as coworkers.

What Oppenheimer Leaves Out About Lt. General Leslie Groves

Nolan's Groves Is Very Close To The Real Man

The Lt. General Leslie Groves in Oppenheimer closely matches the real-life Lt. General Leslie Groves, at least for the years when the atomic bomb was being built. The film does not go into his backstory, nor much of his later life, such as when he retired in 1968 and became the Vice President of Sperry Rand Corporation, a now-defunct aerospace and defense contractor (via AtomicArchive). What Oppenheimer does leave out is that "Colonel" Groves was actually promoted to the rank of Temporary Brigadier General at the outset of the Manhattan Project.

What Matt Damon Has Said About His Oppenheimer Role

Damon Understood The Difficulty A Military Man Would Have With A Group Of Scientists

Matt Damon gave a lot of thought to his portrayal of the General, as any Academy Award-nominated actor should. He said (via MilitaryTimes),

"The frustration [for] Groves — what he lived with as a military person — he suddenly finds himself in charge of a bunch of civilians who don't really recognize the chain of command."

Groves had to handle a town of talented, but arrogant, scientists, and the most talented and most arrogant was the one he personally selected to put in charge of the whole project. It's a much different world than he's used to and Damon works hard to show the frustration and strain put on him throughout. Damon said about his character's relationship with Oppenheimer,

"They both appreciated each other — they helped each other fulfill each other's ambitions. Each couldn't have done it without the other. There was a lot of genuine affection there."

Scenes of that genuine affection between the characters, like right before the bomb test, are some of Matt Damon's best work in Oppenheimer.