For example, there is a moment where James Remar, who played [Henry L. Stimson, Truman’s secretary of war], kept talking to me about how he found out that Stimson and his wife were honeymooning in Kyoto. And that was one of the reasons that Stimson took Kyoto off the list to be bombed.
I made him cross the city off the list because of its cultural significance, but I like, just add that. It’s a wonderful exciting moment where no one in the room knows how to react.
How do you shoot with such a huge cast and so many locations?
Anytime you go into a lot of places, a lot of different actors, it’s always going to be a puzzle. I did insist on planning 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 drew me to the story I alluded to in my last film, “Tenet” [2020]it was this idea that when the scientists did their calculations, they couldn’t completely eliminate the possibility that they could ignite 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? How would that be?
How do they feel about it? You can minimize that and say they thought it was a slight possibility. But having done many giant explosions on film sets myself, where safety is the most important thing, the tension surrounding those ignitions is incredible. It’s very hard for the special effects guys to quantify for us exactly how it’s going to sound, exactly how it’s going to look. So when that countdown comes, it’s incredibly stressful, 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 sense of that, living in that room.
In this case, it worked and the world survived. Who made that calculation?
It came from Teller. One of the few things I changed is it wasn’t Einstein that Oppenheimer went to consult about it, it was Arthur Compton who ran an outpost of the Manhattan Project at the University of Chicago. But I changed that to Einstein.