Already on edge over the past resurfacing, Yeon-jin grows more anxious when she learns about her daughter’s new homeroom teacher — and of a sudden death.

Do-yeong meets with Choi Hye-jeong to find out more about his wife — and her past. Yeon-jin digs into Dong-eun’s private life.

Tormented by her high school classmates and with nowhere to turn for help, Moon Dong-eun sinks into despair before deciding on a new mission in life.