The Backstreet Boys were on Late Night with Jimmy Fallon to promote their new Christmas song on December 19, and while you can watch that below, you're going to want to start with the video up top. Trust me.
VIDEO FLASHBACK - BSB Hits The Grammys in 1999
That's because the Late Night web-exclusive performance is of BSB rocking out to The Roots' take on As Long As You Love Me. Yes, that's right. And I'm not the only one jazzed about them kicking it old school (can't believe this song came out in 1997) as you can tell from the girly screams coming from the audience as soon as they hit the first harmony.
Click play up top and then you can watch BSB sing It's Christmas Time Again.