Charli xcx brings out Chappell Roan for a surprise ‘Boom Clap’ at the Kia Forum

Charli xcx brought Chappell Roan onstage at the Kia Forum in Los Angeles on October 17, and the two performed “Boom Clap,” Charli’s 2014 single, together. It was the first time Charli had played the song live since 2023, and she used the moment of its return to stage a surprise.

The appearance came during Charli’s Music, Fashion, Film tour, and it followed a now-familiar pattern for the run: each night she revisits an older song, and on several stops she has handed part of the moment to a guest. Across the two-night Los Angeles stand, other surprise guests included PinkPantheress, The Dare and Adéla.

A guest she wouldn’t name

Before Roan walked out, Charli set up the cameo without saying who it was, telling the crowd that the choice of song had not been hers.

“Every night on tour, I play an old song,” she said. “I asked a friend of mine if she would come and sing an old song of mine with me, and they said, ‘The only way I’m doing it is if it’s this song,’ so you have her to thank.”

The friend was Roan, one of the biggest new pop acts to break through over the previous couple of years, and the song she had asked for was “Boom Clap” — a track that predates both artists’ current peak and that many in the room would have grown up with. Originally released in 2014, it appeared on the soundtrack to “The Fault in Our Stars” and on Charli’s album “Sucker.”

Why the pairing landed

Surprise duets are a standard tool of the modern pop tour, but they only work when the pairing means something, and this one did. Both artists make unapologetically big, hook-forward pop, and both have spent the last few years being treated as reference points for where the genre is going. Putting them together on a decade-old hit let the audience hear that lineage in a single song.

It also fit the logic of the tour itself. The whole conceit — Music, Fashion, Film — leans on spectacle and on the idea that any given night might hold something you cannot stream later. A one-off guest turn on a song Charli had deliberately shelved for three years is exactly the kind of thing that rewards being in the building, and exactly the kind of thing that travels far beyond it once the clips go up.

For anyone who only knows “Boom Clap” as a 2014 radio fixture, the performance was a reminder of how durable a good pop single can be. More than a decade on, it was still sturdy enough to carry a surprise, a crowd singalong, and a passing of the torch between two of pop’s loudest current voices.