On May 18, 1999, Backstreet Boys released their sophomore album, Millennium. The record would go on to cement the boy band’s legendary status, breaking the record for most album sales in a single week, becoming the best-selling album of 1999, and spawning the fastest-grossing tour of all time.

In honor of Millennium’s 20th anniversary, Jezebel decided to re-examine the ingredients that made the album a certified hit, and see whether or not the Backstreet/*NSYNC rivalry making headlines around that time still holds water.

Watch the video above to hear what resident boy band expert/Backstreet Boys stan Maria Sherman (whose book about boy bands comes out in 2020 under Black Dog & Leventhal, an imprint of Hachette Book Group) and resident *NSYNC superfan Ashley Reese had to say about Millennium’s legacy. “I kind of saw Backstreet Boys as the ballads band. *NSYNC was kind of like the fun party band,” says Reese. “You’re totally gonna bring Backstreet Boys home to your mom.”