JUST ADDED: 5 Seconds of Summer will be rocking the stage at this year's iHeartRadio Music Festival Village in Las Vegas! The band sat down with Ryan Seacrest to break the news. Click here to buy your tickets now, before they sell out!
Taylor Swift is known for having special guests join her on stage while she's on her 'Red' tour. During her stop at the O2 Arena in London, T-Swift brought out the U.K.'s own Emeli Sande, and they performed Emeli's "Next to Me."
Taylor explained to her fans that they met at the Brit Awards last year before they performed the song for the London crowd.
Tonight @emelisande surprised our London crowd with 'Next to Me'!! SHE IS SO HEAVENLY. I've had the best time here. Last show tomorrow....— Taylor Swift (@taylorswift13) February 10, 2014
Check out their duet below!