PHOTO BY MELINDA SUE GORDON / UNIVERSAL PICTURES

At once a biopic and a chronicle of the atomic bomb, “Oppenheimer” has to be history, philosophy and science in one film. No college course would attempt to cover this much material in a semester, but writer/director Christopher Nolan, nothing if not ambitious, tries to handle it in a frantically busy 180 minutes.

He’s successful. The film is strong in many ways, but as a feat of organization, it’s truly impressive.

The sweeping film is mostly presented in retrospective, as a pair of government proceedings interrogate the life and achievements of J. Robert Oppenheimer (Cillian Murphy). His work on the atomic bomb initially made him an unlikely, if regretful, national hero; the intellectual chaos and suspicion of the Cold War undid much of that reputation.

The script is clever to deploy that later context as a framing device, keeping the action mostly in Los Alamos, where Oppenheimer and many of the greatest scientific minds in history were developing the atomic bomb. The portion of the film leading up to the Trinity test — the dread, excitement and hand-wringing that surrounded that moment — are tremendous.

The moments after the bomb is used may be even better. They’re also terrifying.

As Oppenheimer, Murphy carefully portrays the big questions — not just matters of right and wrong, but matters of physics and entirety — that would grow to consume him over the course of his life. Nolan leaves such contemplations to his star, however; the questions the film raises are those of history. This is a movie about the way that World War II faded into the Cold War, the way that the specter of Communism changed world history and about America’s complex place in the 20th Century.

That’s a lot for any movie to deal with. Nolan has hired half of Hollywood to tell the tale, including Emily Blunt, Robert Downey Jr., Florence Pugh, Rami Malek, Jason Clarke, Matt Damon, Casey Affleck and Tony Goldwyn. The endless parade of famous faces lends to the feeling that “Oppenheimer” is a bit overstuffed; while there is more than enough subject matter, it might have been a stronger movie if some sequences and diversions had been left on the cutting-room floor. (The cutting room is a lonely place on a Christopher Nolan movie.)

The sheer power of the movie, however, is enough to override any sense of overindulgence. It is, after all, the most significant moment in modern history. How can you possibly summarize it?

In the case of “Oppenheimer,” quite effectively.

My Rating: 9/10

“Oppenheimer” is now playing in theaters.