Bang Myung-soo is a famous webtoon author. He has writen a webtoon about his four ex-girlfriends which catches the eyes of Soo-jin, a film producer and she decides to make a film based on it. But for all surprise, Soo-jin is one of Myung-soo's ex, and everything turns much more dramatic since his three other ex-girlfriends also come back into his life at the same time.