Sung Hae-sung, who died 12 years ago at the age of 19, comes back. Dressed in a high school uniform, he runs into Ho-bang, who is now 31 and a policeman, and accepts the magical things that have occurred to him. He asks Ho-bang about Jung-won. Working as a sales rep in a clothing store, Jung-won fights with a jerk customer and loses her job. She can’t pay her rent and is even sexually harassed by her landlord. Jung-won believes that it’s her fault that Hae-sung died and always misses him. Hae-sung has returned, but Jung-won already has a boyfriend named Cha Min-jun. The two feel their first barrier caused by the rift in time. They will continue to explore the depth of their relationship as we get to learn why Hae-sung came back.