Get ready for a blast from the past as MBC's 'Infinity Challenge' takes you back to the 90's!

While the episode will air on December 27, pictures from the filming set are already being circulated online as fans of the show just cannot wait any longer!  The actual year-end concert took place on December 18 at the MBC Dream Center with appearances by a lot of the legendary 90's artists, such as S.E.S (with Seolhyun in place of the expectant mother, Eugene), Jinusean, Jo Sung Mo, Cool, Turbo, and more!

Even the cast members of 'Infinity Challenge' got in the mood by dressing up as one of the hottest idol groups at the time, H.O.T--bad hair and outdated outfits to boot. 

Check out the pictures, as well as the bonus S.E.S shot!

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