Kang Hyeon-joong, a former National Intelligence Service agent, is currently running a private investigator office after he quit his previous job. Han Mi-so is his secretary helping him with his daily tasks in the office. One day, Kim Jin-hee comes to the detective’s office and requests him to investigate all the women who follow her husband around. She introduces herself as wife of Jang Joon-seok, CEO of the prominent construction company, Dae-ho Trading. When she started dating her current husband, who used to be a mere frontline employee, her father trained him into a professional entrepreneur and then promoted him to the current position. When her husband became successful, women began pursuing him. She said these women tried to blackmail her husband for money. Kang Hyeon-joong accepts the request and starts investigating the women around Joon-seok. When Kang Hyeon-joong finds out that there is this woman, So-yeon, who sees joon-seok often, he scolds So-yeon. However, she says it is unfair because it is Joon-seok, who is bothering her.

　　Dong-goo, a lowlife thug, has always been living a hopeless miserable life. One day, he accidentally obtains a bankbook with such a large amount of money as much as one billion won. He travels down to Busan in order to try to obtain the PIN number for the bank account. As Dong-goo meets the eight year old boy, Bok-gi (Jo Won-bin), who believes Dong-goo is his dad, and the boy’s mother, Ae-sook (Hong Ah-reum) in Busan, their story begins.

　　Joon Ho is a third year high school student who just finished taking his university exam. His main interest is to sleep with Seo Yeong, his girlfriend, but, so far, she has turned him down.