Dong-eun moves into an apartment in Semyeong that directly overlooks Yeon-jin’s house, literally positioning herself to watch over her enemy's life. The Real-Life Inspiration

While digging through trash for intel, Dong-eun is caught by Kang Hyeon-nam , a housekeeper. Instead of reporting her, Hyeon-nam—a victim of domestic abuse herself—strikes a deal: she will help Dong-eun gather intelligence if Dong-eun helps her "kill" her abusive husband.

As an adult, Dong-eun meticulously gathers information on her former bullies. She discovers their current status: ringleader Park Yeon-jin is a successful weathercaster married into wealth; Jeon Jae-joon manages a high-end boutique; and others have become drug addicts or social climbers.

The "interesting story" behind involves the cold, calculated start of Moon Dong-eun’s lifelong revenge mission against her high school tormentors. Key Plot Developments in Episode 2