Somewhere out there in the cosmic expanse, there's a world where Charli XCX's “Vroom Vroom” was a No. 1 hit in 2016. Turn it up loud enough and you might hear it, too: a magical place where everyday people memorized its lyrics without meaning to, celebrities danced in memes set to its juddering drops, and we were all pleasantly tired of it by New Year's, but no earlier. (Who can forget Bernie's awkward little “beep-beep!” of joy at his victory party in November?)

I don't live there, and, sadly, neither do you. But on Wednesday night, that world fit into the basement of New York's (Le) Poisson Rouge, where a few hundred sparkly, sweaty young people gathered to see the English pop star perform songs from her recent mixtape, Number 1 Angel. They cheered wildly when “Vroom Vroom” arrived midway through her set, crying out “All my life / I've been waiting for a good time, a good time” like they really had been waiting all their lives to find what they'd found right here and now.

This was a crowd whose love for Charli was deep and constant. They cheered the same way for just about every song from the new mixtape, bringing stadium-level fervor to a club performance — even though Number 1 Angel is anything but a conventional stadium-pop project. It's a giddy fuck-you to America's Top 40 mainstream, a quixotic left turn that you can dance to, a pure expression of Charli's artistic id. Seeing it performed live is a surreal thrill.

“I haven't played shows like this in a long fucking time,” she said at one point. “To see all these angels here, that's some next-level shit!” Charli bopped across the stage, a blissful ball of energy, losing herself in the beat to “Roll With Me” and bouncing off the walls to “Bounce.” There was no pretense of choreography to separate her from the crowd; she was us, and we were her. By the time she brought openers Brooke Candy and CupcakKe onstage to close the show with the exhilaratingly profane “Lipgloss,” it felt like a one-night utopia.

Like “Vroom Vroom” and its namesake EP, which were produced by the Scottish firebrand SOPHIE, Number 1 Angel reflects Charli's ongoing fascination with the producers and songwriters who orbit the London-based PC Music label. This year she's adopted A.G. Cook, the label's jester king, as her chief muse, and he accompanied her at the New York show — nominally playing the DJ behind Charli, but just as often wandering out front to flop around like a carefree goofball at a rave while a recorded backing track played on.

Whether this behavior sounds charming to you is an easy shorthand for how you likely feel about the PC Music clique, whose output has sharply divided critics for the last three years. Their radical re-envisioning of pop's digital soul is at least partly meant as a challenge, and it would be a waste of time if it didn't get under some people's skin. What makes their work with Charli so exciting is that they finally have a real-life star putting their theories into practice, making the PC Music philosophy wholly her own and then running away with it. She's the Lenin to their Marx, and the revolution is actually quite fun if you give it a chance.