For all the behind the scenes gems and 80s nostalgia it has on offer, Bao Nguyen’s The Greatest Night in Pop is a masterclass in event planning.

As anyone who has ever tried to cram a group of A-listers – or even a crowd of sluggish friends and family members – into the same room at the same time knows, it’s going to be a headache. Bringing together 46 of today’s musical superstars for a night of unpaid work would be near impossible (small wonder most of today’s chart-topping collaborations involve no more than two artists). “There’s so many managers and publicists and agents that you’d have to go through,” Nguyen said from Sundance, where he premiered his film about the making of We Are the World.

The Greatest Night in Pop functions as a tick-tock of an 11th-hour miracle. When Ken Kragen, the Hollywood manager, got it in his head to put together a mega recording session featuring the nation’s biggest pop stars for a common cause, he had little reason to believe he could pull it off. But Kragen and his organizing committee had a suitcase worth of Rolodexes and a few other tricks up their sleeves. For starters, they persuaded megastars Lionel Ritchie and Michael Jackson to sign on as the songwriters. Rule No 1: Ensure that high-profile individuals are already “attached”, to use the parlance of the self-important.

Another superstar, the legendary singer Harry Belafonte, was the source of the fundraiser’s purpose: to staunch the problem of African famine. And Bob Geldof of the British charity Band Aid came on to share his wisdom regarding musical activism.

The organizers had barely a month to get their vision in place, but by the time the opening credits of Nguyen’s documentary are finished, we’ve seen the faces of Bruce Springsteen, Cyndi Lauper, Bette Midler, Paul Simon and Diana Ross. Coaxed by producer Quincy Jones, and sustained by a midnight supper of chicken and waffles, the group rallied and belted out an iconic earworm, wrapping by sunrise.

The song’s lasting power is partly to do with its brilliantly simple construction. “The chorus part is made for so many different vocal ranges,” said Nguyen. “Lionel and Michael made it so it’s an anthem and you can just sing along with it quite easily.”

The tune is ingrained in the director’s childhood memories. Growing up in Maryland with Vietnamese refugee parents, the song was on constant rotation. More recently, when he visited his parents in Vietnam, where they have since returned, the song came on the taxi radio. “I knew that I had to do this film,” he said.

The project came about as a Covid workaround. In early 2020, when the director and his producer Julia Nottingham released their documentary about Bruce Lee, Be Water, they agreed that their next project would also have to rely on archival footage. Nottingham had a connection with the company that had produced the American Music Awards, the ceremony that had been something of a pre-game before the artists shuttled off to the recording studio. She reached out to the music producer Larry Klein, who turned out to be sitting on scads of video tape that nobody had seen before. “He said, ‘I’ve been waiting 35 years for this phone call,’” Nguyen said.

“I wasn’t sure if I was the right person to tell the story,” the 40-year-old director said. For one thing, he didn’t remember the time the song came out. “And I’ve actually never done a music documentary.” But upon further consideration, the answer became obvious. “I was like, this is such a compelling story. And one of my roles that I see as a film-maker is to discover something new and meaningful and personal.” As he studied the materials, his vision coalesced. “This feels like a heist film. It’s a story with a sense of like, Ocean’s 11,” – with a covert operation to deliver 40-odd of the most famous people on earth to an under-wraps location for an all-nighter.

A rich sense of tension animates the film. As stars streamed into the recording studio, they were greeted by the single rule Jones posed on the wall: “Check your egos at the door.” The humanity on display in the footage – such as when stars started asking each other for their autographs – also had Nguyen hooked. “I feel like it’s so amazing to see all these supernatural people just being so natural.”

By midnight or so, the artists began to flag. Dylan needed extra help hitting his marks. Stevie Wonder suggested the group start singing in Swahili – and an ensuing debate over whether the people of Ethiopia, which was particularly affected by famine, speak Amharic or Swahili will resonate with anybody who has found themselves in a dysfunctional group Zoom.

But they persevered, loosening up and getting giddy, like a gaggle of kids at a sleepover party. For all the personalities packed in one confined space, there was surprisingly little drama. Perhaps that is because the drama occurred offscreen: notable absences were Madonna, who wasn’t invited (the producers picked Lauper over the Material Girl), and Prince, who’d issued a condition that he record a solo in a room by himself – which was denied.

The song raised more than $60m, though Nguyen points out that its impact was far greater, as it put the issue of African famine in the global spotlight. “Obviously today we’re sort of inundated with images of poverty, but I think it really inspired a lot of foreign aid,” – and paved the path for a raft of artist-activists.

Perhaps most miraculously of all, Nguyen isn’t sick of the song. “That was one of the things I was worried about making the documentary,” he said. “But I still love it at the end of the day. I listened to it this morning when I was getting ready.”

• This article was amended on 30 January 2024. An earlier version misnamed Ken Kragen as “Kraven”.

• The Greatest Night in Pop is now available on Netflix