Cillian Murphy delivers a measured and thoughtful performance portraying the figure responsible for developing the bomb that accelerated the conclusion of WWII in the Far East. He embodies the increasingly recognized physicist who learns from Admiral Lewis Strauss—another noteworthy turn by Robert Downey Jr.—that it’s conceivable the Russians also possess an A-bomb. Already, Oppenheimer suspects the Nazis are advancing toward weaponizing the atom, a realization stemming from his earlier education and career which introduced him to leading minds in both the UK and Germany capable of progressing the theory; consequently, he begins urging the American government to initiate its own program—resulting in the birth of the "Manhattan Project." Driven/prompted/motivated by the ambitious "Col. Groves" (Matt Damon), he assembles a talented group of scientific experts at a specially constructed desert location that he names Los Alamos, and over three years—with $2 billion to spend—they dedicate themselves to the science while plutonium and uranium are processed at an irritatingly slow rate. Considering much of this is based on documented history, the plot itself lacks significant suspense. Instead, Christopher Nolan attempts through his writing and direction to flesh out the characters. It becomes apparent that Oppenheimer possesses a certain charm, but he’s also able to inspire loyalty in people with diverse perspectives—not just concerning the science of their project, but regarding the morals and ethics involved in creating something from which, well, you can't retract it. The latter part of this drama concentrates on the subsequent communist-driven witch hunt aimed at discrediting and ruining this remarkable and imperfect individual, raising intriguing questions about who was manipulating whom. It also carries a striking resonance—not just specifically about Oppenheimer—but regarding all those post-event investigations that rarely provide an honest assessment of actions taken in the name of expediency at the time, instead evolving into character assassinations by individuals who did nothing against those who acted and had to bear responsibility. While the pace occasionally helps maintain engagement, the film is overly long; it sometimes feels laborious. Perhaps a fresh perspective on the writing or direction could have tightened things up without diminishing the story's impact. It might be beneficial to advise Mr. Nolan that a three-hour runtime isn’t always necessary! Nevertheless, it's visually stunning. The aesthetics are top-notch and the overall feeling of the film conveys a sense of authenticity. I believe this is best experienced on a large screen to appreciate it as intended. It's thought provoking, intricate, rich in character—and certainly worth seeing.

Source on TMDB