Taylor Swift was the surprise guest at a concert by the British band The 1975 in London on Wednesday night -- and she gave the debut performance of her number-one single, "Anti-Hero."
Last summer, The 1975's frontman Matty Healy told Pitchfork that Taylor had heard their latest album Being Funny in a Foreign Language before it was released, and he, in turn, had heard her album Midnights before it dropped. The two artists share a producer, Jack Antonoff.
Healy later said in an interview that the band actually worked on Midnights but their contribution didn't make the final cut. However, it seems the two artists are still tight: In addition to Taylor joining The 1975 to play "Anti-Hero" on acoustic guitar, she also performed their song "The City," from The 1975's 2013 self-titled album.
Taylor wore a mirrored mini dress for the performance, which Rolling Stone notes is her first live performance since her appearance in September at the Nashville Songwriters Association International Awards.
You can see fan-recorded clips of the performance on social media.