‘Oppenheimer’ Review: Christopher Nolan’s Explosive Historical Epic

“This isn’t a new weapon. It’s a new world,” someone remarks as J. Robert Oppenheimer develops the atomic bomb in “Oppenheimer,” a brainy and breathless exploration of the rise and fall of a physicist dubbed, not without reason, “the most important man who ever lived.” Like Prometheus, the mythic figure to whom he is compared here, Oppenheimer suffered for his works, bedeviled from within and without. So a story that is essentially about a scientist who spent his life writing equations becomes, in the expert hands of writer-director Christopher Nolan, a boiling cauldron of drama.

Mr. Nolan’s utterly enthralling film lasts three hours. But despite being as talky as a math seminar, it crackles, hurtles and whooshes, generating more suspense and excitement than anything found in the alleged climaxes of the recent superhero pictures (which owe much to the director’s Batman films). Adapting “American Prometheus,” the Pulitzer Prize-winning biography by Kai Bird and Martin J. Sherwin, Mr. Nolan has thought intensely about how to turn arcane material—not one person in 100 could explain the details of Oppenheimer’s method—into a popcorn movie, despite it containing only one spectacular scene.

“Oppenheimer” is divided into two parts. One is “Fission” (events as seen by the title figure, intensely brought to life by Cillian Murphy with grave arrogance). The other, “Fusion,” is set off by black-and-white imagery and centered on the scientist’s antagonist years after the war, a political figure named Lewis Strauss played by Robert Downey Jr. , who puts his considerable charm on hold and assumes a startling midcentury look. Characteristically, Mr. Nolan chops up time to tell a nonlinear story, keeping most scenes to only a few minutes, as he wanders through the imaginations and memories of these two figures, one of whom perhaps does not deserve quite so much attention.

There’s no question which part of the film is more dynamic and involving: The study of Oppenheimer’s life, the development of the bomb and his accompanying self-flagellation about what he unleashed are all magnificently realized. Mr. Nolan does not get enough credit for his writing, but his screenplay should be taught in film schools. He turns abstractions into easily grasped images (at the Los Alamos laboratory, a large glass bowl gradually fills with marbles to indicate U.S. progress toward reaching its goal for enriched uranium), illustrates character in memorable yet succinct ways (Oppenheimer demonstrates genius when he visits Europe to give a physics lecture, opens his mouth and speaks fluent Dutch, a language he did not know weeks earlier), and packs both meaning and wit into crystalline lines of dialogue. The Danish physicist Niels Bohr ( Kenneth Branagh ) is revered among specialists, but to explain his importance to the rest of us, Mr. Nolan has someone ask, “How many people do you know who proved Einstein wrong?” Many of Mr. Nolan’s most sparkling lines go to the general overseeing the Manhattan Project, delightfully played by Matt Damon as the avatar of the try-anything American who combines easygoing confidence with self-deprecation: “I wasn’t confused before, but I’m certainly getting there,” he says, speaking for some in the audience.

The interspersed other part of the film is not as compelling, though Mr. Nolan evidently feels it depicts a major injustice vital to understanding Oppenheimer and his times. The chief drama here is the 1954 decision of the Atomic Energy Commission, amid a Red Scare, not to renew Oppenheimer’s security clearance after questioning his (many) ties to Communists, a matter linked to a betrayal by Strauss and the latter’s own failure to be confirmed in 1959 as secretary of commerce—the first Senate rejection of a cabinet appointee since 1925. Each of these situations triggers an ersatz trial, hence lots of courtroom-style sparring. But considering Oppenheimer’s mammoth creation, the details surrounding the withdrawal of a security clearance (a decision reversed posthumously just last year) and the fate of an obscure cabinet appointee seem like grains of sand compared to a mountain. Moreover, Mr. Nolan doesn’t sufficiently clarify the motives behind Strauss’s Judas turn. (A dispute over exporting radioactive isotopes is involved, though you may miss it.)

Such choices do not, however, prevent “Oppenheimer” from being one of the few standout works of cinema released this decade. Its centerpiece—the July 16, 1945, Trinity test in the New Mexico desert that proved both that the bomb worked and that it would not set the entire world afire—generates a level of awe, based in historical pre-eminence rather than fantasy, that we rarely experience at the movies anymore. Amid the ensuing celebration of the grim deployment in Japan of the two A-bombs, instruments of slaughter that nevertheless probably saved hundreds of thousands of lives, Mr. Nolan beautifully captures what was going on inside Oppenheimer’s tortured mind: pride, triumph, horror.