Lucky guests to a private party in Stockholm on Sunday witnessed what a guitarist calls "a piece of music history." Swedish band ABBA performed together for the first time in decades, marking 50 years to the day that band members Björn Ulvaeus and Benny Andersson first met, reports Sweden's Expressen. At one point, female members Agnetha Faltskog and Anni-Frid Lyngstad took to the stage to perform "The Way Old Friends Do," but were soon joined by Ulvaeus and Andersson, who sang along. Pictures of the event are spreading online, but so far no videos have surfaced. As Mashable puts it, "ABBA performed for the first time in 30 years AND NO ONE RECORDED IT?"
ABBA—which has sold almost 400 million albums—broke up in the early 1980s and last performed together in 1986, while honoring manager Stig Anderson, report the BBC and CBC. In the years since, they were reportedly offered $1 billion for a reunion tour, but "they were talking about 120 gigs or something," Andersson said. "It would have taken 10 years out of my life." In 2008, Ulvaeus assured fans "you'll never see us on stage again," with Faltskog later adding that the band belonged in the past. "It was such a long time ago, and we are getting older, and we have our different lives," she said. However, Sunday's concert was "absolutely amazing—a lot of emotions," says Lyngstad. "It's been very nostalgic." (Read more ABBA stories.)