Some of the biggest stars in the music industry gathered in Hollywood on the day after the Grammys for an even bigger occasion: to record a new version of “We Are the World,” designed to benefit Haiti in the wake of that country’s devastating earthquake, as well as mark the 25th anniversary of the original collaboration. “It’s no accident this happened,” said producer Quincy Jones of the convergence of auspicious date and important cause.

This year’s recording took place in the same studio as 1985, on the lot of the former A&M (now Henson) Studios. Jones was back behind the producer’s podium, alongside the song’s co-writer, Lionel Richie; original engineer Humberto Gatica was behind the dials. R&B singer Mya started a rumor (and immediately took it back) that the song’s original bridge — memorably sung by its other co-writer, Michael Jackson — would remain. But there were nods to 2010, too: Lady Gaga producer RedOne polished the backing track with a more contemporary sound, and Crash director Paul Haggis was on hand to shoot a new video. “The eyes of the world are finally on Haiti,” he said. “We cannot allow it to be forgotten again.”

Haggis’s words were echoed more personally by Haitian native Wyclef Jean, who reminded the assembled group that had he not come to America, he’d be one of the kids in the videos of earthquake survivors surrounding the choir as they recorded. “When I got in the music business, my whole life changed. Today, it represents what the whole mission was for me,” he told the group, by way of an introductory pep talk. “What’s bigger than a contribution is the fact that you lent your voice. The fact that you lent your voice means that we are going into the 21st century Haiti, and I promise you we are not going backwards.”

A small sampling of the 81 performers in attendance: Celine Dion, Barbra Streisand, Miley Cyrus, Kanye West, Jennifer Hudson, Justin Bieber, P!nk, Julianne Hough, Carlos Santana, Tony Bennett, Brian Wilson and Al Jardine of the Beach Boys, Rob Thomas, Randy Jackson, Jamie Foxx, Ann and Nancy Wilson of Heart, and your newly anointed Best New Artist, Zac Brown. Jeff Bridges bonded with Vince Vaughn.  The Jonas Brothers chatted up Jennifer Nettles and Kristian Bush of Sugarland. Two celebrity daughters, Nicole Richie and Rashida Jones, underscored the passing of time since the original session; Nicole even brought her daughter. Plenty of folks brought flip cams, including Snoop Dogg, whose singing voice Brandy called “hilarious.” For Natalie Cole, the event allowed her to both gawk and fit in. “As celebrities, we’re fans of one another,” she said. “So we’re all lookie-looing in there, getting autographs and numbers. It’s really cool. We kind of get a chance to be normal for a couple hours.” When Usher rolled in at 5:30 p.m, he was, truthfully, just another megastar. There was a sign outside the original recording that read, “Check Your Ego at the Door,” and according to Josh Groban, that humble vibe continued. “It’s inspired chaos,” he said. “It’s great to see so many legendary artists sweating it out and doing it until its over. To be smack dab in the middle of a sandwich between Barbra Streisand and Weezy was an experience I don’t think I’ll ever have again.”

By 6 p.m., the choir had run through the chorus at least a dozen times, and took a ten-minute break that turned into 45. On a large screen set up in the courtyard, the masses of personal assistants and publicists and managers lingering during the session (and the civilians who’d gathered on the street outside the complex) were treated to a live feed of Streisand recording the same line over and over and over and over. For the record, it was “There’s a choice we’re making / We’re saving our own lives / It’s true we’ll make a better day / Just you and me.” “I didn’t come all this way to sing one line,” Babs said at one point; they then allowed her to vamp some improvisations over the chorus. Other acts pulled out to sing solo lines were Bieber (riffing on the chorus melody in his earnest teensy way), Groban (“We can’t go on / pretending day by day…” as well as providing what he called “the token classical note of the vamp”), and Dion, who was coached by Lionel Richie to let her inner gospel diva out. “You’re honored that they pick you for the hardest part of the song, but at the same time it gives you a lot of pressure, so thanks a lot,” she joked. “The rhythm was changed a little bit and I so wanted to make it perfect. They played the track, and on my right shoulder, Lionel Richie. I was like, ‘I think I’m in good hands.’”

It was Dion who sparked the evening’s most thrilling moment, a spontaneous a capella group singalong of “Lean On Me.” It was not immediately clear what the plan was for the night’s biggest head-scratcher, a pair of stand-ins wearing full green-screen body stockings. By 8 p.m., folks were starting to trickle away — the Jonas Brothers had a very important softball game — but a vast chorus still remained, clapping and laughing and singing those familiar words again and again, wanting it to be just right, the video screens surrounding them still running non-stop disaster footage, as though anyone needed reminding. “We have to help each other,” Dion explained of the night’s real purpose. “It’s an honor to have been asked, and a responsibility to act and make a difference. When something terrible happens, it’s not time to cry. It’s time to join each other and act. We are making the best and feeling every word of it to make a difference. But we will make a difference, so yes, we are enjoying ourselves.”