TEEN TOP's Niel and Changjo will be collaborating with old-school teen idol Kim Won Joon on an upcoming episode of 'Immortal Song'.

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According to an insider on July 28, the three handsome stars will be teaming up against other stiff competition on the well-known performance show. Niel and Changjo helped out Kim Won Joon with a modern cover of his old-school hit "After Everybody Sleeps".�

In other news, TEEN TOP successfully wrapped up their promotions for their album 'Natural Born TEEN TOP' last month and are preparing for their coming solo concert on August 1-2.

Stay tuned for this TEEN TOP-Kim Won Jun collaboration!