If anyone arrives at the Oscars gala – next Monday morning – with at least one statuette virtually guaranteed, it is Christopher Nolan, who in the previous days has won the award given by the union made up of his colleagues, the Golden Globes, Critics Choice and Bafta. It is quite likely that as a producer he will also win the award for best film, and that he will lose in the category of best adapted screenplay, in which the favorite is Cord Jefferson. But even if he can’t take it all, this will undoubtedly be Oppenheimer’s year, a well-deserved recognition of a cinematic phenomenon who left nearly $1 billion at the box office with a smart, risky proposition about a chapter key in human history.

Have you become a fan of nuclear physics with the movie?

I have no more appreciation for it than an ordinary person. But it’s true that I got involved in this project because of my interest in quantum physics from the collaboration with Nobel Prize winner Kip Thorne, who worked with me on Interstellar and Tenet. Robert Oppenheimer and his contemporaries were involved in a transformation of scientific thought based on Albert Einstein’s theory of relativity. This was one of the most important paradigm shifts in human thought. My job when adapting Prometeo americano, the great book by Kai Bird and Martin Sherwin, was to be clear about what the themes were and to understand the physicists’ point of view, but without confusing the audience. No one will leave after seeing Oppenheimer become a professional quantum physicist.

Was it complex to adapt this book to the big screen?

The big plus is that Kai Bird and Martin Sherwin wrote 700 pages based on research that Sherwin had devoted 25 years of his life to. I found in the text, certain moments, great possibilities for a film, even if it was not a book intended for this. I had a huge source of information to work with, the only research I did outside of the book was reading the records of the hearings that Lewis Strauss did in the Senate, and also the Oppenheimer security sessions, which I got a thousand page transcript.

It’s a lot of material…

My process was actually taking notes based on my readings of the book, thinking about what I would tell people about this topic if I were at a dinner party, to try and capture their attention. What are the really important things? What is it about the story that moves me? And from then on I began to develop a structural approach and intersperse the different narratives, that of Lewis Strauss with that of his opponent, Robert Oppenheimer. That’s how I came to have a first draft, and when I started to rewrite it, I took everything that was in that first version as if it had all been made up, as fiction.

The film shows who Oppenheimer is and what he is forced to do, a recurring theme in his filmography.

I am drawn to characters that the audience can identify with, particularly if they are far from perfect. I felt very comfortable in the world of action cinema because I was working with Batman, who interested me more than other superheroes because he is a human being who has many conflicts. My fascination with Oppenheimer lies in the fact that public discourse did not necessarily match practical behavior. What he said was one thing and what he did was another. For example, he never apologized for the feelings generated by the use of the atomic bomb. He never tried to justify himself with excuses. He took charge of something that he defined as a technical success. But everything he did after 1945 reflects that he was someone who carried a good deal of guilt, a clear awareness of what his invention had caused and the ways in which it had changed the world, not necessarily for the better. It seemed to me that he was a very powerful protagonist to be the axis of a cinematic story.

The cast he summoned is impressive. Was it complex to find the actors, the protagonists and the secondary ones?

I needed unique faces with a particular energy for all the minor roles. The amount of people involved in the Manhattan Project is part of its importance. I wanted to show this wide diversity of faces and personalities. For me, as a director, it was exceptional to be able to work with them, because they were able to research the real people they were playing, and they came to the set as real experts on who they had to play. Each of them knew more about who those people had been than I did. This made it a real pleasure to work with them. And in the scenes where there are a lot of scientists, we allow ourselves a lot of improvisation. I was able to tell the group to dare, to have a discussion.