Watch Charli XCX join Billie Eilish on “Guess” at the Los Angeles show

Billie Eilish welcomed Charli XCX to the stage at the Kia Forum in Los Angeles last night for a surprise performance of their hit song “Guess.” The energetic track comes across Brat and it’s completely different, but still Bratthe remix edition of Charli XCX’s album.

Charli XCX took the green-lit stage for the performance, earning loud screams from the audience before Eilish joined in with her verses.

“Guess” was not originally released bratbut made it into the subsequent deluxe edition instead Brat and It’s the same but There’s Three More Songs Also It’s not. Eilish was there for a remix Brat and it’s completely different, but still Bratwhich arrived in October. The song is nominated for a Grammy in the Best Pop Duo/Group Performance category.

Eilish is currently on the road on her Hit Me Hard and Soft tour, which includes two more nights at the Kia Forum this month before wrapping up in the US. She travels to Australia in February before heading to Europe in April.

Charli XCX, meanwhile, recently announced that she will be headlining five shows before appearing at Coachella next spring. The musician was previously on tour brat alongside Troye Sivan on the co-headlining Sweat Tour, but this time she’ll be hitting the arenas alone. The brat The tour begins April 22 in Austin and continues with shows in Minneapolis and Chicago. The final two shows in the series will take place on April 30 and May 1 at the Barclays Center in Brooklyn.