Even if you’re not a Friends fan, you’ve probably heard the song “Smelly Cat,” which actress Lisa Kudrow’s character, Phoebe Buffay, wrote and performed on the show. Taylor Swift is a fan of the show, as well as a well-known cat lover, which made it perfect for Kudrow to join Swift onstage Wednesday night to perform a duet of “Smelly Cat” during Taylor’s final L.A. show.

As you can imagine, the crowd loved it -- especially when Lisa/Phoebe stopped Taylor in mid-song to offer “pointers” on her performance, much like she did when Pretenders lead singer Chrissie Hynde guest-starred on a 1995 episode of Friends. Kudrow loved it too, tweeting after the show, “That was fun. Thanks Taylor.”