Bobby Brown, *NSYNC and the Backstreet Boys Turn Out for First 'Boy Band' Live Show


Boy band members of the world unite!

Thursday's episode of Boy Band officially kicked off the live shows -- and boy did it have an intro to remember! Fans were greeted with a special appearance by Bobby Brown, *NSYNC's Chris Kirkpatrick and Backstreet Boy A.J. McLean during the show's opening moments.

WATCH: EXCLUSIVE: Nick Carter Spills on His Backstreet Boys Past, New Series 'Boy Band' & His Son's Musical Future!

The live show began with the contestants singing "Candy Girl" by New Edition, which Brown was an original member of from 1978-85. They then transitioned to New Kids on the Block's "You Got It (The Right Stuff)." The audience went wild when Nick Carter serenaded his co-star Emma Bunton by singing the Backstreet Boys' hit song "I Want it That Way" and was joined by McLean.

But the fun didn't stop there! *NSYNC's Chris Kirkpatrick made an appearance when the guys sang "Bye, Bye, Bye," before finishing off with One Direction's "What Makes You Beautiful." (Sadly, no 1D member was in attendance.)

Following the opening number, McLean took to Twitter to share a pic with Kirkpatrick. "Ain't no party like a #BoyBand party! East Coast.. @BoyBandABC goes live right now!!," he wrote.

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During the live shows, viewers at home will vote live for their favorite five band members to create their ultimate boy band. Carter, Bunton and multi-GRAMMY Award winner Timberland are the Boy Band "architects," helping to select the finalists and build the group.

ET spoke with Carter
before the series debuted and he dished on his role in the creation of the ultimate boy band.

"The architect's job is really to mentor these kids. We're not competing with one another," Carter explained to ET's Leanne Aguilera during a recent set visit. "We're trying to find common ground with each other and to pick out the best talent from these 30 kids and make the right choice along with America."

See more on what Carter had to share about the show in the video below.