In March 2016, AC/DC frontman Brian Johnson announced that, per doctor’s orders, he’d be taking a break from touring due to severe hearing problems. “I am hoping that in time my hearing will improve and allow me to return to live concert performances,” he wrote in a lengthy, heartfelt statement. “While the outcome is uncertain, my attitude is optimistic. Only time will tell.”

Time has proven to be on his side, as Johnson made his triumphant return to the stage on Sunday. The classic rock legend made a cameo during Muse’s set at Reading Festival, performing the 1980 AC/DC hit “Back in Black”. Check out footage up above.

The surprise performance marked Johnson’s first time doing an AC/DC song live in over a year. This past spring, he covered “Money (That’s What I Want)” alongside Robert Plant and Bad Company’s Paul Rodgers in Oxford.

“Such an honor to have the legendary Brian Johnson join us onstage at Reading Festival last night,” Muse posted on Instagram today, along with a pic of Johnson reveling in the moment and the crowd’s rapturous applause.

Upon Johnson’s departure last year, AC/DC carried on touring with Axl Rose as replacement. It’s unclear whether Johnson’s return means he’ll be joining the band live again.

See more clips and pictures from the momentous night, including one in which Muse frontman Matt Bellamy gives Johnson a huge hug.