Love is like a car accident. Summer first met Kim Geun on a midsummer crosswalk when he heroically saved a child in the street, rushing late for school.
That day, Geun handed her a discarded composition notebook and said, ""Your lyrics are amazing! You have real talent."" With his bright smile, Summer's long-hidden first love began.
Years later, now a famous singer-songwriter, Summer falls into a slump and visits the university Geun attends.
While avoiding attention, she impulsively asks him to film her music video. As they navigate the precarious line of friendship, will Summer finally confess the feelings she has cherished for years?
