Out of many contestants, one individual who went by the name of 'Mystery Circle' stood out amongst everyone else. In the very first round, the singer faced off against 'Pyramid Man' to sing Psy's "Napal Baji". The audience and the panel were shocked by the unique sound of 'Mystery Circle' which kept them guessing who the talented artist could possibly be.

Accordingly, 'Mystery Circle' moved on all the way up to the third round where he sang TVXQ's heartwarming song "I Believe". The song aligned extremely well with the soothing voice of the singer behind the mask that everyone in the studio simply listened in awe. Unfortunately for the singer, the third round would be the last on this day as the 'Flame Man' moved onto the final round.

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The time to reveal the mysterious singer finally came and when the mask was removed, no one could hide their shock as they saw 2AM's Jo Kwon standing on the stage! Check out all the performances!