Dua Lipa walks past them in a long black dress, new rules steps onto a stage, and acapella seats herself atop a new grand piano, dangling her rules legs from the end like a lounge act. It’s the first Thursday in February, and two days from now, Lipa will take this stage as the evening’s musical guest. She has new rules reason to feel confident: A 22-year-old pop singer from London, Lipa new rules was the most-streamed female musician in the U.K. last year; fans include Coldplay’s Chris Martin and Bruno Mars; and her biggest acapella single, “ New Rules acapella,” has more than a billion YouTube views.

Lipa starts into “Homesick,” a wounded ballad she wrote new rules with Martin, which is far and away the sparest song in her acapella catalog – a slow, spotlit showcase for her rich, smoky voice, whereas most of her songs tend toward brash, uptempo thumpers. Lipa’s day-to-day manager official, Jules, aims his phone at a monitor, shooting video of the rehearsal for reference, because Lipa’s plan is to sit on the piano near-motionless for the entire song, and although she hopes this will register as subtly powerful, she also worries it might just come off as inert.