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.

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

While Ha Do-yeong comes across an intriguing game opponent, Yeon-jin realizes her deepest secrets are at stake when she tries to intimidate Dong-eun.

Son Myeong-o's sudden absence causes tension in the friend group. Dong-eun finds her trust in Kang Hyeon-nam tested.

Yeon-jin threatens Hyeon-nam after discovering her involvement with Dong-eun. Yeo-jeong devises a way to get the truth out of Yeon-jin.

Yeon-jin and Shin Yeong-jun panic over Myeong-o. Dong-eun takes care of a lingering problem. Yeon-jin’s mother schemes to remove a threat.

Do-yeong issues an ultimatum. Dong-eun demands a piece of evidence be handed over. Yeon-jin attempts to do damage control after old videos appear online.

As the final pieces of Dong-eun's revenge plot slot into place, she considers what comes next — and what it will mean for Yeo-jeong.