Backstreet's back ... with Florida Georgia Line? The popular '90s boy band appears to be working on a duet with one of country's hottest duos. A series of cryptic Instagram posts from each member of the Backstreet Boys on Monday (June 27) hint at a collaboration, but exactly what remains a mystery.

At first, BSB member Brian Littrell posted a photo from the studio teasing that the band is, "Doing something we've never done before.... BSB feature with FGL..... Great record.... Comes out late August....."

It's unclear if Littrell is talking about the band's own record, but FGL's Dig Your Roots does come out Aug. 26. After some teasing from other band members of a "surprise collaboration" and "secret project," both Nick Carter and Howie Dorough confirmed a possible duet.

"In the studio with my @backstreetboys recording a song for @flagaline new album," Carter captions a photo.

While Florida Georgia Line haven't confirmed or denied the possible collaboration, the duo have become friendly with Carter as of late. The boy band member caught the band's set at CMA Fest and posed for a photo. Meanwhile, last month a video of Florida Georgia Line covering the Backstreet Boys in concert surfaced on the internet in which the duo confessed that the boy band shaped their early music discovery.

“Backstreet Boys was my first concert,” Brian Kelley told their audience in South Dakota. “There you go, big surprise!”

Tyler Hubbard had BK’s back when fans laughed in disbelief. “Don’t laugh,” he said pointing to a fan in the crowd. “Don’t laugh at us!”

“You big bullies!” Kelley chimed in.

Hubbard later admitted that the Backstreet Boys album was the first record he ever bought, too. “BK, sometimes I think that we are the Backstreet Boys,” he admitted.

Maybe Hubbard will get his wish of being a Backstreet Boy, if only for one song.

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