With Park Yeon-jin’s wedding on the way, Dong-eun’s revenge rolls out according to plan. Meanwhile, a fateful encounter at a hospital takes place.

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

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.