Swedish pop music group and cover band, A*Teens, rose to fame with their hit singles "Mamma Mia" "Dancing Queen" and "Upside Down" -- landing on the top 10 Swedish music charts and the U.S. Billboard top 100 in the late '90s - early 2000s.

After performing together for 6 years, the group -- who consists of Marie Serneholt, Dhani Lennevald, Amit Paul and Sara Lumholdt -- parted ways in 2004. The foursome reunited 20 years later at the Swedish music competition show "Melodifestivalen" ... and most recently performed in Chile.

"Upside down bouncing off the ceiling, inside out stranger to this feeling, got no clue what I should do, but I'll go crazy if I can't get next to you!"

Guess what they look like now!