“It wasn’t that much of a rivalry,” joked Emily Blunt, during a bit of onstage cross-talk with Ryan Gosling at the Oscars – and she wasn’t far wrong when it came to winning awards. Blunt, who appeared in Oppenheimer and was nominated for best supporting actress, and Gosling, the now legendary Ken in Barbie, traded a few gags at the microphone, but there was no getting away from the reality: as far as the Oscars were concerned, the A-bomb film had nuked the walking-talking-doll movie.

A winner in seven categories including best film, best director and best actor, Oppenheimer is the first authentic blockbuster to dominate the Academy Awards since The Lord of the Rings: Return of the King in 2004. Its $960m worldwide box office dwarfs such apparently “popular” films as Everything Everywhere All at Once ($111m) and Argo ($227m). While it’s fair to point out, as Gosling did, that it rode “Barbie’s coat tails all summer” as part of #Barbenheimer, Oppenheimer’s box office results are possibly even more impressive than Barbie’s $1.4bn, given the essentially dour nature of its narrative and themes, and its three-hour running time.

Oppenheimer’s ability to thrill audiences over such operatic length is yet another feather in its cap, given its sparing deployment of such Christopher Nolan standbys as colossal explosions or vertiginous visual effects. Instead the film leans on exceptional performances, notably from its two acting Oscar winners: Cillian Murphy as scientist J Robert Oppenheimer, and Robert Downey Jr as Lewis Strauss, the slippery former head of the Atomic Energy Commission. As Nolan’s film flips between time periods, a uniformly strong cast articulate the exhilarations, crises, and ambiguities contained in what was a momentous era.

So how did the film pull off such a staggering success? Oppenheimer, in relative terms, may have been a slow-burn commercially, and was hammered by Barbie on their shared opening weekend in July, but it gradually piled up the revenue thanks to director-screenwriter Nolan’s approach to his material and how this piqued audiences.

A veteran film-industry PR executive, who did not wish to be named, said Oppenheimer ticked all the right boxes. “A well-made film, well reviewed, of the moment, with an important issue that has horrible relevance today. And it did huge box office and, in so doing, was a lifeline for cinemas. Therefore it’s a feelgood vote for Academy members. Barbie is a phenomenon, of course, but in the final analysis lightweight.”

These do seem to have been the deciding factors in the Oscars race. Back in the summer, Barbie looked set to clean up, with its smart comedic chops and beautifully detailed design. It also had the extra oomph, in diversity-conscious Hollywood, of showcasing a stellar female writing-and-directing job from hitherto three-time nominee Greta Gerwig. But the Oscars tends to reward more weighty, message-bearing work. You could also argue that Poor Things got the nod for funny and stylised, and there wasn’t room for two at the ball, so Barbie and Gerwig got squeezed out.

A figure with gravitas, if not exactly possessed of knock-’em-dead showmanship, Nolan was one of those directors with a big name who, hitherto, had never quite got his ducks in a row for a serious Oscar bid. But that changed this time around, with a release pattern that included a moneyspinning run in Imax theatres, and an awards campaign that concentrated on the director’s technical and craft abilities as well as his outspoken love for the moving image and theatrical screening. A vote for Oppenheimer began to look like a vote for the film industry itself.

Furthermore, once campaigning got going, it soon became clear that Oppenheimer was the one to beat. The film’s team made sure Nolan was front and centre, points out Rich Cline, chair of the film section of the London Critics Circle, which runs its own high-profile awards. “They didn’t do anything out of the ordinary as far as campaigning goes. They were pretty much in line with what all the other films were doing. But Nolan was the focus and they were making sure he was recognised for his considerable achievements. He’s a quiet person in the industry, and he stuck his head above the parapet and went out and appeared at things he doesn’t normally do. It was nice to see him out and having a good time.”

An awards campaign usually comprises countless personal appearances and onstage interviews at special screenings, as well as TV chatshows and print interviews. Then there’s the subtle art of the rolling acceptance speech, in which a suitably judged address from the winners podium can act as a pitch to voters for the next prize. Nolan proved adept at this, even uncorking a bit of a comedy personality. He told a funny story against himself while accepting a prize from the New York film critics, about his Peloton instructor slamming one of his earlier (unnamed) films. He even turned a hosepipe on TV host Stephen Colbert before participating in a Benny Hill-style chase.

“They worked incredibly hard,” says the PR exec, “keeping the film in voters’ minds long after its opening, and persuading Nolan to be so much more present and out there than ever before. Cillian Murphy also decided to go way beyond his comfort zone.” But, adds the exec, campaign buzz has to be managed correctly. “Volume alone does not cut it. You have to judge the mood. Look at Cate Blanchett last year for Tár – unusually for her, she literally did everything and I think it was too much for voters. The idea of her as best actress was being rammed down their throats.”

Over the years, Nolan has built up an authorial brand with his superhero films and elaborate sci-fi movies, a brand burnished with his more recent excursion into history and real-life. One of the reasons Nolan is often compared to Stanley Kubrick is because he has produced distinctive, challenging and personal films fully inside the Hollywood studio system, commanding large budgets and significant box office results. Added to which, his role as a saviour of theatrical releasing – particularly by insisting on putting Tenet out at the height of the Covid pandemic, while cinemas were reeling – earned him a lot of love. Moreover, Cline points out, #Barbenheimer “reinvigorated cinema” when things were still looking desperate.

The Oscars are perhaps still remorseful for never giving Alfred Hitchcock or Kubrick a directing Oscar, and for failing to give Steven Spielberg and Martin Scorsese one until they’d made 15 and 20 films respectively (and the latter for a film, The Departed, that didn’t really hold a candle to all-time masterworks such as Taxi Driver, Raging Bull or Goodfellas). Fortunately for Nolan, the awards season groupthink quickly got behind him as a director – though few felt obliged to vote for his screenplay, interestingly – with wins at the Golden Globes and Baftas. “The time was right for Nolan,” says the PR executive. Cline agrees, saying: “The Oscars like to recognise people they really admire after years of work – so this was a chance to say to Nolan, ‘You are one of the greatest film-makers working today and it’s time for you to win some awards.’”

Surprisingly, maybe, for a film-maker so attuned to cinema’s technical possibilities, Oppenheimer’s weakness turned out to be in the craft categories: it won best cinematography and best editing but lost out in costume, production design and sound, the kind of areas it would need to have picked up if it was going to challenge the record of 11 Oscars, jointly held by Return of the King, Titanic and Ben Hur. In the end, the seven it did win meant that, in Oscar terms, Oppenheimer was big, but not that big.

While Nolan appeared to have best director locked in, best picture was a slightly more open field. For a while, Poor Things looked like it had a serious chance, but the divisive dispute over its copious sex and nudity meant that mustering enough of the electorate became less and less of a possibility. The Zone of Interest, Past Lives and Anatomy of a Fall all – superficially perhaps – resembled films that had done well at the Oscars in previous years. “They were all serious films about serious things,” says Cline, “and beautifully crafted. Any of them could easily have won in the past. Past Lives went home empty handed, which is shocking when you think how good that film really is.”

In retrospect, the key indicator of Oppenheimer’s future triumph lay in it scooping up awards from the US craft guilds: the Screen Actors Guild, the Directors Guild of America, the Producers Guild. All of these have significant voter overlap with the Academy. “The voters for the Oscars are industry people,” says Cline, “and Oppenheimer has been winning all the industry awards. That’s the industry voting for itself and they are basically saying, ‘This is what the film industry is for – we are not only here to make beautiful art films, we are here to make big, big movies about big, big things – things that are huge successes at the box office as well. All of that combined in Oppenheimer.”

Read more about the 2024 Oscars:
• Here’s our news wrap and full list of winners – now read Peter Bradshaw’s verdict
• Al Pacino, British mothers and a codpiece envelope: the real winners and losers of the night
• Relive how the ceremony unfolded with our liveblog and get up to speed with the top viral moments and the best quotes of the night
• Have a gander at how the stars looked on the red carpet and at the show