Seven years ago, Sun Hwa (Sung Hyun-ah) was the girlfriend of Heon Jun (Kim Tae-woo). Moon Hao (Yoo Ji-tae) was Heon Jun's junior, and Moon Hao had always had a crush on Sun Hwa. Soon, Heon Jun went abroad to study, and Sun Hwa and Moon Hao started dating, but they didn't end up together. Seven years later, Heon Jun returned to China after completing his studies and became a director. He found Moon Hao, who was teaching at a university, to meet up with him. At this time, Moon Hao had already started a family. During the conversation, they gradually talked about their past love - Sun Hwa. They both wanted to see Sun Hwa again, so the two decided to go look for Sun Hwa together. In the process of looking for their old love together, the two men began to have an inner struggle again.