Christopher Nolan says he wrote Oppenheimer script in first person

Filmmaker Christopher Nolan says he wrote the script of "Oppenheimer" in first person perspective as he wanted to give the audience a direct peek into the mind of his titular protagonist.

The director, known for acclaimed films such as "The Prestige", "The Dark Knight" trilogy starring Christian Bale, and "Inception", said this was the first time he penned a subjective story for the screen.

"I actually wrote in the first-person, which I've never done before. I don't know if anyone's ever done it before. But the point of it is, with the colour sequences, which is the bulk of the film, everything is told from Oppenheimer's point of view  you're literally kind of looking through his eyes," Nolan told British magazine The Empire.

Starring Cilian Murphy as the titular theoretical physicist regarded as one of the fathers of the atom bomb, the Universal Pictures project is based on the Pulitzer Prize-winning book "American Prometheus: The Triumph and Tragedy of J Robert Oppenheimer" by Kai Bird and the late Martin J Sherwin.

Once he sent the finished screenplay of "Oppenheimer" to his visual effects supervisor Andrew Jackson, the director said he told his associate that "we have to find a way into this guy's head".

"We've got to see the world the way he sees it, we've got to see the atoms moving, we've got to see the way he's imagining waves of energy, the quantum world. And then we have to see how that translates into the Trinity test. And we have to feel the danger, feel the threat of all this somehow.' My challenge to him was, 'Let's do all these things, but without any computer graphics'," he said.

"There's the idea of how we get in somebody's head and see how they were visualising this radical reinvention of physics. One of the things that cinema has struggled with historically is the representation of intelligence or genius. It very often fails to engage people," he added.

It was important for him, Nolan said, to not judge Oppenheimer for his decisions.

"I wanted to really go through this story with Oppenheimer; I didn't want to sit by him and judge him. That seemed a pointless exercise. 

"That's more the stuff of documentary, or political theory, or history of science. This is a story that you experience with him  you don't judge him. You are faced with these irreconcilable ethical dilemmas with him," he explained.

"Oppenheimer" also stars Emily Blunt, Matt Damon, Robert Downey Jr, Florence Pugh, Rami Malek, Benny Safdie, Josh Hartnett, Dane DeHaan, Jack Quaid, Matthew Modine, Alden Ehrenreich, David Dastmalchian, Michael Angarano, Matthias Schweighofer, Gary Oldman, Harrison Gilbertson, Emma Dumont, Devon Bostick and Trond Fausa.

Shot with IMAX film cameras, the movie is scheduled to be released in theatres on July 21.