Overview: Jaegyeong puts the puzzle pieces together of the day Joonseo died, and a rift between Jongsoo, Taejin, and Jiyeon pushes them apart. Meanwhile, Jaegyeong, Yoonjin, and Joosong visit Hyeonwoo, discover the whole story between Joonseo and the medication incident, and then find a clue to the murder at the mill.