The 28-year-old singer joined in on Horan's performance of 'Slow Hands.'
We can guarantee Taylor Swift's fan's weren't ready for this!
The 28-year-old singer treated the crowd at London's Wembley Stadium on Friday to a surprise appearance by Niall Horan, who came out to perform his hit, "Slow Hands" with her. Friday's concert is the first of two dates Swift has in London as part of her Reputation tour.
"Soundcheck at Wembley Stadium with this guy @niallhoran THANK YOU for surprising the crowd tonight!!! ? @GarethCattermole @hogieaaa @GettyEntertainment," Swift captioned a slideshow of images of herself and Horan having fun during rehearsals on Instagram.
Fans, meanwhile, went wild on social media, freaking out over the surprise.
Swift has brought out BFF Selena Gomez, Troye Sivan and Shawn Mendes as surprise guests on previous Reputation dates.
Fans may remember Swift's brief romance with Horan's former One Direction bandmate, Harry Styles, at the end of 2012. While the relationship didn't work out, it reportedly inspired Swift's 1989 songs, "Out of the Woods" and "Style."
"I mean, I don't know if they're about me or not…but the issue is, she's so good, they're bloody everywhere," Styles said in a 2017 interview with Rolling Stone. I write from my experiences; everyone does that. I'm lucky if everything [we went through together] helped create those songs. That's what hits your heart."
"In writing songs about stuff like that, I like tipping a hat to the time together. You're celebrating the fact it was powerful and made you feel something, rather than 'this didn't work out, and that's bad,'" he added. "And if you run into that person, maybe it's awkward, maybe you have to get drunk...but you shared something. Meeting someone new, sharing those experiences, it's the best s**t ever. So thank you."
Swift is now dating British actor and model Joe Alwyn. See more in the video below.
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