Miserable and unsuccessful, Ban Ha Ni, a single 37-year-old woman who is generally servile and timid, thinks she's lost all her spark. Holding only a temporary position at her work, she’s fearful of being let go at any moment, and considering her current lack of security, she also does not want to remain single. She lives her life like that going about it day by day, until one day, her spunky younger self appears in front of her demanding change. Her 17-year-old version of herself travels from the past to meet her current self, and the 17-year-old Ha Ni is nothing like the current 37-year-old Ha Ni. Bright and optimistic, she's the complete opposite of what Ha Ni is like today. (Source: Netflix, AsianWiki; MyDramaList)