The Backstreet Boys made a surprise appearance during Florida Georgia Line's set at the 2016 iHeartRadio Music Festival on Saturday night (Sept. 24), with the two groups performing BSB's hit "Everybody."

Before bringing the Backstreet Boys out, FGL's Tyler Hubbard and Brian Kelley reminisced about the first concert they attended and the first CD they bought, which just so happened to be by the '90s boy band. Then, they started singing: “Everybody, yeah / Rock your body, yeah / Everybody, yeah / Rock your body right / Backstreet’s back, alright!"

Readers can press play above to watch FGL and BSB's onstage collaboration, which, judging by the crowd's reaction, was a hit.

Hubbard and Kelley team up with the Backstreet Boys on their new album, Dig Your Roots, as well: Together, they sing "God, Your Mama and Me." Hubbard calls it "such a well-written song. A song that, when we heard it, we fell in love with it."

"We never really heard it said that way, you know, and heard it put that way," he adds, "but it’s so true, and that’s how we felt about our wives and just naturally drawn to that song."

The all-genre 2016 iHeartRadio Music Festival ran Sept. 23-24 at Sin City’s T-Mobile Arena. Sam Hunt was also part of the event; he performed on the opening night (Sept. 23) and at the festival’s Daytime Village on Sept. 24.

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