(Paris) Christopher Nolan is back where we least expected him, on the terrain of the biopic, revisited in his own way in Oppenheimer, a film which paints a tortuous portrait of the American who developed the atomic bomb.

Highly anticipated, the film, which will be released in theaters on Wednesday, retraces in 3 hours the key moments in the life of Robert Oppenheimer (1904-1967), a physicist who marked the history of the United States and the 20th century, and contributed to bring the world into a new era: the nuclear era.

As usual, the author of the action blockbuster Tenet, the war film Dunkirk or the astral epic Interstellar is deploying enormous resources, with film shooting in new formats (including black and white Imax ), for a blockbuster with a complex construction and claimed visual ambition.

The title role is played by Irishman Cilian Murphy, a regular on Nolan’s sets and also known for the Peaky Blinders series. Emily Blunt plays his wife Kitty, Matt Damon plays Leslie Groves, the general responsible for supervising the manufacture of the bomb, and Robert Downey Jr. plays Lewis Strauss, a politician who will precipitate the fall of the physicist.

At the heart of the film, the scientific epic of the race for the atom, on the secret base of Los Alamos (New Mexico) where, in the middle of World War II, scientists and soldiers of the Manhattan Project are busy developing the bomb before the Nazis.

This handful of men is both aware of crossing a point of no return for humanity, by equipping it with a weapon capable of destroying the entire planet, and galvanized by the prospect of ending the world conflict. And perhaps, by deterrence, to any form of war in the future.

The highlight is the first test of the bomb, dubbed “Trinity”, and reproduced in the New Mexico desert without digital effects, but with old-fashioned special effects, one of Christopher Nolan’s trademarks. .

With CGI, “it’s hard to instill fear. So I challenged my teams to deal with the real, analog world,” Christopher Nolan told AFP during a meeting in Paris. “What we needed was to try to give our audience a sense of what it was like to be there” when the first nuclear explosion occurred, the 52-year-old filmmaker continued.

On set, at the time of the explosion, “we all felt…what that moment meant in history. We kind of felt it in our flesh,” Cilian Murphy added. The 47-year-old actor said he prepared for six months to embody the inventor of the atomic bomb.

A rich and very complex role, as the film, adapted from a very detailed biography (Robert Oppenheimer, Triumph and tragedy of a genius, by Kai Bird and Martin J. Sherwin, Le Cherche-Midi) wants to explore the dilemmas, contradictions and multiple facets of a man whose secrets have never been revealed.

An ambivalent character, crushed by responsibility and doubt after the nuclear attacks of August 6 and 9, 1945 in Hiroshima and Nagasaki which claimed at least 210,000 victims and were presented by the United States as necessary to end the war, Oppenheimer is also one of the most famous victims of McCarthyism, in the midst of the Cold War.

Honey for Nolan, who loves nothing more than mixing temporalities, stories and playing with paradoxes, at the risk of confusing. Alternating black and white and color, to reflect the subjectivity of certain scenes told from Oppenheimer’s point of view, the filmmaker stages crucial hearings in the life of the physicist, illustrating his setbacks faced with an administration launched into the hunt for communist sympathizers.