We initially track Oppenheimer’s rise through academia and the dizzying formation of relationships with other great thinkers of his time, while also getting glimpses of a later hearing in which a much older Oppenheimer is coming under fire for his liberal beliefs and suspected ties to Soviet Communism. A third storyline (shot in black and white) introduces us to Lewis Strauss (Robert Downey Jr.), the one-time head of the Atomic Energy Commission, and now up for a Cabinet post in Dwight Eisenhower’s second administration. Strauss’ connection to Oppenheimer gradually becomes clearer as the film moves along.
It’s frankly almost impossible to keep track of the who’s-who of historical figures here, including hydrogen bomb creator Edward Teller (Benny Safdie), Nobel Prize-winner Ernest Lawrence (Josh Hartnett), quantum theorist Niels Bohr (Kenneth Branagh), and physicist Richard Feynman (Jack Quaid), among many others. We also meet the two major women in Oppenheimer’s life: psychiatrist and Communist activist, Jean Tatlock (Florence Pugh), and Oppenheimer’s eventual wife Kitty (Emily Blunt), neither of whom do much, although Blunt gets a rousing scene in support of her man near the film’s end.
It’s when word comes that the Nazis are working on their own version of the atomic bomb—and that President Franklin D. Roosevelt has approved the United States’ own fast-track development of such a weapon—that the tension and momentum in Oppenheimer ratchets upward. As Oppenheimer and his fellow physicists toil away on the theories behind the bomb and whether it could work, the scientist is placed in charge of its actual development by General Leslie Groves (Matt Damon), who’s impressed by the breadth of Oppenheimer’s knowledge and some heretofore unseen qualities of leadership.
It’s a gamble for that will come back to haunt Groves later, given that Oppenheimer’s progressive leanings, as well as his indirect dalliance with the American Communist party, although he was never officially a member, are well-known and viewed with some suspicion in many quarters of the government. Some of his ideas—like eventually seeking to avoid building an even bigger “super” bomb derived from a hydrogen reaction—are met with incredulity.
Yet Oppenheimer, Groves, and their team race forward to complete the bomb before the Germans can, even as they try to contain the flow of information outside Los Alamos (where the military has literally built a town to keep everyone on the project in one place) and grapple with the moral implications of what they are devising.
Nolan’s masterful skills at cross-cutting, the building of tension, the interplay of music and sound, and the maximum use of the IMAX 70mm compositions he and cinematographer Hoyte van Hoytema deploy all come to the fore during this central portion of the film, creating a genuine sense of dread and urgency as the date draws closer and the pressure gets stronger to test whether the bomb will work. The urgency arises from the drive to end the war once and for all while the dread surfaces from the fact that no one really knows what will happen when that button is pushed.