“Oppenheimer” introduces its protagonist in crisis mode. He’s studying abroad and terribly homesick, unable to sleep, and mocked by his teacher. That mockery leads the young scientist to do the unthinkable: poison the apple sitting on the teacher’s desk. It’s a risky way to introduce your main character, and Nolan is immediately signaling Oppenheimer’s fractured mental state — he’s brilliant but tormented, as if he’s constantly trying to solve some problem in his overactive mind. From here, Nolan is off to the races, jumping in and out of two distinct timelines. The main timeline, shot in color, is told entirely from Oppenheimer’s point of view, giving us the story as he saw it (or as Nolan, adapting the book “American Prometheus” by Kai Bird Martin J. Sherwin, imagined he saw it).
The second timeline, filmed in black and white, zeroes in on another character: Lewis Strauss, the former U.S. Atomic Energy Commission chairman, as he undergoes a cabinet post hearing in the 1950s. Played by Robert Downey Jr., Strauss is our window into a different view of Oppenheimer; an outsider looking in. Downey Jr., who has been too busy with Marvel stuff to appear in many other movies (except “Dolittle”), is electric in the part, trading in his usual mannerisms for a more reserved, mysterious character. We can’t quite crack what Strauss is about and why the film is focusing on him so much, and that’s because Nolan is playing the long game. He’ll get there eventually.