"What's the number of the house you are living in right now?" Newspaper editor Eun Seo lives in Seoul alone. When the contract to her house is almost over, but she can't find another house she likes, she decides to live with her father in her hometown for a while. Jin Cheol, her father, is a locksmith who is on 24-hour standby in Incheon and still lives in the house where his family used to live. Eun Seo's family has left their 'home' and found their own homes. Eun Seo ends up alone with her dad and finds the traces of her family she's been forgetting while she's at home, and through her, Jin Cheol opens up to the family that he's been shunning away.