Yi-jun stays prickly but starts trusting Jae-hee. Jae-hee notices something suspicious about the milk Yi-jun was drinking and realizes he is being threatened. The investigating team thinks the perpetrator could be someone else. Jae-hee finally gets the chance to enter the room that's been banned from entering. She searches for the missing phone in the room but immediately faces danger.
Casts:
Yim Si-wan, Seorina, Kim Jung-hyun, Yeon Woo, Ryu Seung-soo, Park Jun-myun, Jeong Han-seol, Kim Do-yoon, Jung Yoo-min, Kim In-kwon, Kim Ki-bang, Nam Hae-jun, Ahn Sang-woo, Choi Jin-ho, Hong Eun-hee, Park Ah-in, Cho Seung-yeon, Lee Young-jun, Jeon Yeong, So Yi-han