The long-awaited new work will be screened in theaters as a medium-length animation in the summer of 2023! Along with the summer brass band competition, the ensemble contest, commonly known as "Ancon," is a place where exciting performances are held. The performance of several people in one group has a charm different from that of a competition. In order to participate in the Kyoto prefectural tournament of Ancon, a representative team is selected in the school's preliminary round. However, with over 50 members, the Kitauji High School brass band is facing a variety of problems! Will Kumiko, the newly appointed head of the club, be able to make it through the preliminary rounds? The days of struggle begin.