Introverted classical pianist and top student Kaoru Nishimi has just arrived in Kyushu for his first year of high school. Having constantly moved from place to place since his childhood, he abandons all hope of fitting in, preparing himself for another lonely, meaningless year. That is, until he encounters the notorious delinquent Sentarou Kawabuchi.

Sentarou's immeasurable love for jazz music inspires Kaoru to learn more about the genre, and as a result, he slowly starts to break out of his shell, making his very first friend. Kaoru begins playing the piano at after-school jazz sessions, located in the basement of fellow student Ritsuko Mukae's family-owned record shop. As he discovers the immense joy of using his musical talents to bring enjoyment to himself and others, Kaoru's summer might just crescendo into one that he will remember forever.

Sakamichi no Apollon is a heartwarming story of friendship, music, and love that follows three unique individuals brought together by their mutual appreciation for jazz.