“I’m writing because my father forced me to” - this is how the amazing story of Eunyu, a teenage girl, into whose world her father’s future wife unceremoniously bursts into, begins. Eunyu writes a letter to herself to read it in a year. She is sure that during this time nothing will change in her sad life, unless her father finally moves away and now will not tell exactly what happened to her own mother, whom she has never seen. However, the incredible happens: a letter sent in 2016 is received by a girl named Eunyu, who lives back in 1982, and a correspondence begins across time. They are separated by decades, but this does not prevent them from becoming true friends. Strong emotions and sincere confessions of the heroines, more and more poignant from letter to letter, ultimately lead both to the same truth...