As Nam-soon assists Hee-sik in his drug investigation, she has a run-in with the ominous Ryu Si-o. Ri Hwa-ja plots her revenge against Nam-soon.

Hee-sik witnesses the jarring effects of the drug when it strikes his team leader. Nam-soon's search for evidence garners attention from foes.

Geum-ju pays a strategic visit to Si-o, who has his own motives. During a birthday dinner, Nam-soon's family questions her growing kinship with Hee-sik.