It finally happened: a Backstreet Boys and *NSYNC crossover.

AJ McLean and Nick Carter of Backstreet Boys teamed up with Joey Fatone and Lance Bass of *NSYNC to form the supergroup of all boy-band supergroups: Back-Sync. They debuted Friday night at Bingo Under the Stars, a Pride event benefiting L.A. Pride and the Trevor Project.

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*BSYNC performed the hits “Backstreet’s Back”, “Bye Bye Bye”, and “I Want It That Way” with original choreography.

“It’s interesting to have the four of us knuckleheads do something together, which you’ve never seen before,” Fatone told Variety. “BSB fans are very loyal, so we’re going, ‘We get it — certain people liked one band or the other back in the day, but now it’s okay to like both.'”

“We were just on stage going, ‘Maybe we should do a supergroup and tour and do an album,'” Carter added. “We’ve come together for a cause greater than ourselves, so let’s let it blossom into something.”

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McLean chimed in, assuring all members of Backstreet Boys and *NSYNC they were welcome to join.

“Fans still want a Backstreet/*NSYNC tour, but it’s got to be all 10 of us,” McLean said. “It’s the only way to make it work, so I think he’d be sleeping on it if [Timberlake] didn’t do it, but he’s a dad doing his thing and I completely respect that. This four is a dream team right now.”

Superfan Blake Lively gushed over the performance on her Instagram Story.

“True story: I just watched this until Instagram finally cut me off by pausing the video,” she wrote. “Because even they knew it was too much for me to handle in one sitting.”

Back-Sync - Photo: Blake Lively/Instagram
Back-Sync – Photo: Blake Lively/Instagram

Lively added that her husband Ryan Reynolds is painfully aware of her boy-band obsession.

“Also, a true story. My husband sent this to me. He understands the significance. God bless him.”