Campus couple Sang-yeol (Kim Myeong-joong) and Mi-na (Lim So-mi) are a married couple who maintain their living as a magazine reporter and pretty famous writer. Sang-yeol, who is always at home writing, has been in an affair with his neighbor and collegemate Da-yeong (Hwang Jeong-ah) for quite a while. Then one day, Mina runs into Da-yeong and exchanges phone numbers. Mina starts to suspect the frequent phone calls to her husband from an unknown number. She finds out Da-yeong is the one he's bee...