The drug infiltrates Nam-soon's family — prompting a search of the source and an antidote. A mourning Hee-sik furiously goes after Si-o's inner circle.

Si-o learns of Geum-ju's ruse and decides to expand his target. As the drug case becomes more intense, Hee-sik asks Nam-soon to move in with him.

To find out Nam-soon's identity, Si-o narrows down his search and goes after her family. Hee-sik faces harsh discipline after news of the drug goes wide.