For example, there’s a moment where James Remar, who played [Henry L. Stimson, Truman’s secretary of war], kept talking to me about how he learned that Stimson and his wife had honeymooned in Kyoto. And that was one of the reasons that Stimson took Kyoto off the list to be bombed.
I had him crossing the city off the list because of its cultural significance, but I’m like, just add that. It’s a fantastically exciting moment where no one in the room knows how to react.
How do you shoot with such a giant cast and so many locations?
Anytime you get into myriad locations, a lot of different actors, it’s always going to be a puzzle. I did insist on scheduling it around Cillian’s haircut. [Laughs] Because I’m very allergic to wigs in movies. I really wanted the film to not have any obvious artifice when it came to the way characters presented themselves.
One of the key moments that really hooked me on the story, which I referred to in my last movie, “Tenet” , was this idea that when the scientists did their calculations, they couldn’t completely eliminate the possibility that they might set fire to the atmosphere and destroy the world. And they went ahead and pushed that button. But my feeling was, what if you could be in that room? What would that be like?
How do they feel about that? You can minimize that and say they thought it was a tiny possibility. But having done a lot of giant explosions on film sets myself, where safety is the absolute most important thing, the tension around those ignitions is unbelievable. It’s very hard for the special effects guys to quantify to us exactly how it’ll sound, exactly how it’ll look. So as that countdown comes, it’s incredibly tense, and extrapolating that to the Manhattan Project, to the Trinity test, I couldn’t even imagine. I was excited to try to give the audience a feel of that, to live in that room.
In this case, it worked and the world survived. Who did that calculation?
It came from Teller. One of the few things I’ve changed is it wasn’t Einstein who Oppenheimer went to consult about it, it was Arthur Compton who directed an outpost of the Manhattan Project at the University of Chicago. But I shifted that to Einstein.