The rock star John, 72, and Egerton, 29, the actor who played him onscreen in the hit movie musical, reunited onstage Thursday for the world premiere of "Rocketman Live In Concert" at Los Angeles' Greek Theatre.
The two sat on stools to sing "(I'm Gonna) Love Me Again" before Egerton made his own request.
"I've sang a few times with Elton John," Egerton said from from the stage. "But there is one song we have never done live, and I think we should do it now."
With that, the two gave a full-throttle duet version of "Don't Let the Sun Go Down," featuring the sunglasses-wearing John perched behind the piano and Egerton flinging his arms about passionately as he belted the famed lyrics.
The giddy look on Egerton's face as he walked off the stage pumping his fists, as seen on a photo he posted on Instagram, said it all. "We had a good time," Egerton wrote in the caption.
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"Rocketman Live in Concert" featured the entire film played on giant screens in the outdoor theater, with the Hollywood Symphony Orchestra providing the music.
Following the film, John's longtime collaborator Bernie Taupin took the stage to pay tribute to his writing partner of more than 50 years. "This music is what keeps us alive and we are just getting started," said Taupin.
Jamie Bell, who plays Taupin in the film, "Rocketman" director Dexter Fletcher and Bryce Dallas Howard, who plays John's mother Sheila in the film, also took the stage in the movie reunion.
"Thanks, Mom," John said, hugging Howard as she walked onstage.
Egerton is earning Oscar buzz for his role as John, which explains the timing of the concert as awards season looms. The Welsh actor did not give a speech.
"But I just want to say that working on this film has been the greatest creative episode of my life," he said.
On Saturday, Egerton gave thanks for a week in Los Angeles which included seeing Brandi Carlisle sing Joni Mitchell's album "Blue," Egerton singing for his hero Mitchell, and then performing with Elton John (with Mitchell in the audience.
"I’m not sure what I did in a former life to deserve all of this but I’m loving every minute," Egerton wrote on Instagram. "I feel truly lucky and hope I never wake up."
This article originally appeared on USA TODAY: Elton John, Taron Egerton duet for 'Rocketman' live concert, reunion