Fitz and the Tantrums were wrapping up the tour for their third album last year when their label, Atlantic Records, told them that their song HandClapwas climbing the charts in South Korea. “We were shocked,” says Lisa Nupoff, one of the group’s managers. The Los Angeles-based pop band had never been there, or anywhere in Asia for that matter. But by April of 2018, HandClap had topped the international charts in the world’s sixth-largest music market, outperforming Camilla Cabello’s Havana, the most popular song in the world last year. A couple months later, the song surpassed 1 billion streams in China—even more than it had received in the U.S.