[SPOILERS AHEAD] Park Ji Yoon acted as the detective while Sojin played the role of waitress Miss So, and Jang Jin was in the role of DJ Jang. A Pink's Eunji was a top student residing in the guest house in which owner Lee Eun Sook was murdered. Kim Ji Hoon acted as a painter/pawnshop owner.

Jang Dong Min commented, "The room was locked with coal briquettes burning. If the keys are still there, that should lead the way to the culprit. If there are no keys, it's a locked-room murder case," and suspected top student Eunji.

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DJ Jang went on to check and see if the guesthouse owner Lee Eun Sook was the only one who had keys, while Eunji pointed at Sojin after discovering a past photo. Artist Kim searched through victim Lee Eun Sook's room and realized someone had already been inside. Detective Park Ji Yoon also seemed suspicious of Eunji after finding an article about the death of the top student's parents due to a coal briquette accident.

Lastly, the ratio was 5:2, determining straight-A student Jung as the murderer. Check out clips from the broadcast above and below!