Backstreet Boys Shut It Down at ACM Awards With Florida Georgia Line -- Tim McGraw, Carrie Underwood Lose It!

This video is unavailable because we were unable to load a message from our sponsors.

If you are using ad-blocking software, please disable it and reload the page.

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.

WATCH: 2017 ACM Awards Performers: Luke Bryan, Miranda Lambert, Dierks Bentley, Backstreet Boys and More!

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.

RELATED: Watch the Backstreet Boys Adorably Surprise Their Wives in Florida Georgia Line’s Swoonworthy New Video!

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

RELATED: 2017 Academy of Country Music Awards -- The Complete Winners List

Then Carrie Underwood and Keith Urban got real into it:

WATCH: Nicole Kidman, Keith Urban, Faith Hill & Tim McGraw Are the Ultimate Squad at ACM Awards -- Watch Them Dance!

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!

After the performance, Hubbard and Kelley spoke to ET's Nancy O'Dell backstage and gushed about working with the boy band.

"They've got timeless hits. They’re staying creative, they’re staying busy, they’re staying fresh and they've got great attitudes," Hubbard said. "We've really created a cool bond and almost mentorship at times, too... We've shared some success thus far, but I think the friendship more than anything means a lot to us, it really does."

EXCLUSIVE: Backstreet Boys Treat Their Career 'Like a Marriage' -- 'We Go to Counseling'