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.

After securing the services of an amateur sleuth, Dong-eun uncovers scandalous secrets that she leverages for the next phase of her scheme.

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.