Ariana Grande has some real diehard fans, and in an episode of The Tonight Show With Jimmy Fallon the singer surprised a few with an appearance.

“I’m here with the one and only Ariana Grande, and we’re gonna do something really fun here in the next room,” Fallon said while standing next to a smiling Grande. “We have some of Ariana’s biggest fans, and they’re gonna do a cover thinking it’s a fan video. What they don’t know is that she’s actually right next to them, listening live, and we’re gonna surprise them.”

One by one the singer surprised each fan, and it was such a treat to watch.