If you haven't heard of S.E.S. – Sea (Bada), Eugene, Shoo –then you're unaware of one of the most important groups in K-pop history. It's been nearly 20 years since they debuted, and around 13 years since their last release, but these girls were the OG female idol group for K-pop! 

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Debuting in 1997 under the careful management of Lee Soo Man and SM Entertainment, the trio became an overnight sensation, captivating audiences with a deadly combination of sweet voices, pretty faces, and a charismatic stage presence.

Bada, Eugene, and Shoo have switched up their style consistently over their 5-year career, as they went from cutesy-innocent to urban to sleekly mature. Of course, the changes weren't just superficial - it was first and foremost a reflection of the trio's growth as musicians. With their first two albums, 'S.E.S.' and 'Sea & Eugene & Shoo', the trio were naturally marketed with an innocent, almost angelic image. The girls would prance about the stage with pompoms in their hair, singing about naive (if not charmingly optimistic) confessions of love.

Things started to get interesting with the release of their third album, 'LOVE'. In an attempt to shed their suffocating 'innocent' image, the girls dyed their hair orange and yellow - a move that was considered daring for the time, as both the music industry and the audience were more conservative back then. Although the girls still sang pop songs, they successfully managed to experiment with various styles - natural, mature, sexy/dominant, and urban. Because of their solid success, executives believed that they were good enough to enter the Japanese market under Avex Trax. Unfortunately, their reception was lukewarm at best. Nevertheless, the move set a precedent for future generations of pop stars, mainly fellow SM Entertainment artist BoA.

The group sought separate careers in 2002. Leader Bada signed with JIIN Entertainment. While her first solo work had a strong reception, her subsequent work suffered low sales. Nevertheless, she's still highly respected in the music industry as a great vocalist. She's also starred in numerous musicals, and having taken a liking to them, continues to build upon her craft. Interestingly enough, she's decided to shed her 'Bada' stage name and utilize her real name, Choi Sung Hee. Eugene also left SM in order to sign with another agency, PFull Entertainment. After releasing two solo albums, she's decided to redirect her career towards acting. She also got married and started a family. Shoo started acting in musicals and performed well enough to land a few acting roles in dramas. Shoo also released a mini-album in 2010 and started a family of her own a few years later.

A legendary group that every K-pop fan should be made aware of. Make sure to look them up on YouTube and check out their numerous other tracks that weren't covered here.