'Mask King' introduced another amazing main vocalist from an idol group this week.

During the June 10th episode of 'Mask King', an idol under the mask of 'Cassette Girl' sang a duet with another singer 'CD Player' in the first round. For their performance, they covered Girls' Generation's "Run Devil Run" but added a groovy flair that made everyone naturally dance to the song.

Unfortunately for 'Cassette Girl', she was unable to surpass 'CD Player' and revealed her identity. The entire studio was shocked to see Lovelyz's main vocalist Jin standing on the stage giving her own rendition of Taeyeon's "Can You Hear Me".

Did you know Jin was the one who was under the mask?