After 40 Years, Abba Takes a Chance With Its Legacy

How one of the biggest pop groups in the world secretly reunited to make a new album and a high-tech stage show featuring digital avatars of themselves — from 1979.

STOCKHOLM — The small, tranquil island of Skeppsholmen holds a handful of the Swedish capital’s artistic treasures: Moderna Museet, the theater group Teater Galeasen and the converted red brick warehouse just steps from a waterfront promenade where Benny Andersson has his personal studio. He tucked a packet of the oral tobacco snus in his mouth as Bjorn Ulvaeus sipped coffee in one of its sunbathed rooms earlier this month, the two musicians surrounded by a grand piano, a small selection of synths and an assortment of framed photographs that were perched behind a computer screen.

For the first time since the Reagan administration, the pair were discussing a new album by their band, Abba — an album one of the biggest international pop acts in history somehow made in secret, with all four of its original members congregating nearly four decades after giving their last public performance.

“We took a break in the spring of 1982 and now we’ve decided it’s time to end it,” the group said in a statement in September. The response was thunderous. “Abba is another vessel, isn’t it?” Ulvaeus marveled at the studio, just steps from the larger one where they completed their clandestine LP. “We did this thing and we are on the front page of every paper in the world.”