Shion Hagino is a 29-year-old beauty consultant. Although she has never had a boyfriend, Shion leads a happy and fulfilling life. However, one day, Shion participates in a blind date party and it triggers a flashback where she was rejected by her first love back in high school, who told her, "If you're going to confess, you should at least do something about your appearance". As if drawn back by her past trauma, Shion somehow goes back in time and becomes a 17-year-old high school student again. Using the makeup techniques she has honed, Shion decides to move towards a different timeline as compared to what happened 12 years ago.
In the present day, the local government of Katori City is in the process of sponsoring a taiga drama about its famous historical figure Tadataka Ino, who is known for being the first person to make a map of Japan in 1821. During the process of of making the drama series, a surprising fact is discovered about the first map. That fact is that Tadataka Ino was not the person who made the first Japanese map.