Set in the 1990's, the drama centers around a female high school student Shi Won, who idolizes boyband H.O.T and her 5 high school friends in Busan. As the timeline moves back and forth between their past as 18-year-old high schoolers in 1997 and their present as 33-year-olds at their high school reunion dinner in 2012, where one couple will announce that they're getting married.