See Lance Bass join Backstreet Boys onstage in Vegas

Lance Bass helped shape the pop music landscape of the late ’90s as part of *NSYNC, and Saturday night, he reunited with another iconic boy band when he joined the Backstreet Boys onstage at their Las Vegas residency, titled Larger Than Life after their 1999 single.

The Backstreet Boys’ official Twitter account shared a video that shows Bass hanging out onstage with Nick Carter, A.J. McLean, Kevin Richardson, Howie Dorough, and Brian Littrell while they sing 2000’s “Shape of My Heart.”

The Backstreet Boys kicked off their Vegas residency — which features a slew of singles from the quintet’s discography — on March 1. It’s scheduled to end on July 1 after 26 total shows.

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Though both BSB and *NSYNC once battled for chart dominance, their perceived rivalry — which Carter previously told BuzzFeed was concocted by a bored media — is seemingly far behind them. In April 2016, Bass and fellow *NSYNC alum Joey Fatone belted a live rendition of the Backstreet Boys’ hit “I Want It That Way,” which reached No. 6 on the Billboard Hot 100 in 1999.