1. NSYNC in 1999...
...and in 2013, helping their old pal Justin Timberlake receive the MTV VMA Video Vanguard Award.
2. The Backstreet Boys in 1995.
And the Backstreet Boys in 2016.
3. 98 Degrees in 1998...
...and 98 Degrees in 2016.
4. New Kids on the Block hangin' tough in 1989...
...and NKOTB all dressed up circa 2015.
5. One Direction at the premiere of Harry Potter and the Deathly Hallows: Part 1 in 2010...
...and four-fifths of One Direction in 2016.
Oh! And there's Zayn Malik!
6. Bel Biv Devoe in 1990.
And Bel Biv Devoe in 2014.
7. LFO in 1999, presumably not eating Chinese food.
And here they are now. (Lead singer Rich Cronin died from leukemia in 2010.)
Devin Lima (left) and Brad Frischetti (right).