With their 20th anniversary since debut up ahead, S.E.S have started working on their reunion album.

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On October 25, an insider revealed members Bada, Eugene, and Shoo began recording the first track for their 20th anniversary album last week. They've currently wrapped up recording one song.

Leader Bada also shared the above photo on Instagram with the message, "We're trying to create a meaningful time together with our 20th anniversary ahead. Though we've always prepared in our hearts, I started getting nervous ever since we started discussing details."

As previously revealed, S.E.S' founding label SM Entertainment is heading the production and concept for their upcoming album and concert.

Stay tuned!