A high school boy Ken'ichi lives happily with his mother Hisako, who works for a department store owned by the father of his friend, Noboru. Ken'ichi wins a music contest, and he and his friends form a band, Za Tenputāzu (The Tempters). Ken'ichi becomes upset when he learns that Noboru's father is in love with Hisako, and he leaves home with his band members and music instruments. While he stays away from his mother, he learns from Hisako's friend that Hisako is not his real mother.