The 'Running Man' cast members and guests Oh Yeon Seo, Kim Ji Hoon and A Pink's Eunji were excited to receive an invitation to participate in a concert series, as they were all veteran genius musicians themselves!

However, when the concert members start getting picked off one by one, the game changes entirely - to figure out who within them is the criminal, and stop him or her before it is too late!

With various brain-wracking clues scattered about the premises, the cast members struggle to make sense of the drama unfolding around them. If any person is confident about who the criminal is, they have the option of phoning in to a hotline and calling out that person - but at great risk: if they're wrong, they will be eliminated themselves! Meanwhile, the criminal is still loose, taking out members one by one.

Who is the evil criminal bent on getting revenge on his or her fellow musicians? Check out the full episode below.

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