Backstreet Boys shut it down at ACM Awards with Florida Georgia Line -- Tim McGraw, Carrie Underwood lose it!

The Backstreet Boys go country!

The boyband brought the house down with their collaboration with Florida Georgia Line at the Academy of Country Music Awards in Las Vegas on Sunday night.

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Nick Carter, Kevin Richardson, AJ McLean, Howie Dorough and Brian Littrell first performed their duet with Florida Georgia Line, "God, Your Mama and Me," before getting the crowd on their feet with a slightly country-ish version of their hit, "Everybody," as Carter descended from the stage to rub elbows with country royalty.

See photos from the ACMs 2017 red carpet:

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Everyone proceeded to lose their minds, starting with Nicole Kidman and Faith Hill:

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Then Carrie Underwood and Keith Urban got real into it:

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And then Tim McGraw absolutely lost it when Florida Georgia Line's Tyler Hubbard and Brian Kelley started doing a little Backstreet Boys choreography:

Backstreet's back, alright!

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