Kumiko enters Kitauji High School having been unable to forget what Reina said at a middle school concert band competition. She goes to visit the concert band at school along with classmates Hazuki and Sapphire, where they meet Reina again.

Kumiko and the others join the concert band, and they choose their instruments. Their eccentric senior, Asuka, still likes to mess with them.

Kitauji High School Concert Band is preparing their parts for the ensemble, but some students are fooling around when they should be practicing.

The concert band receives their marching band uniforms and begins marching practice in preperation for SunFes. Things are different now, with the members all more engaged in practice. And SunFes day arrives.

Starting this year, the band holds auditions for members participating in the competition. First-year Hazuki has a chance, too. The bass section does everything they can to encourage her.

The band is hard at work preparing for the audition and the competition. Aoi has trouble with her part, to which Taki says, "when will you be better by?"

The band is abuzz with talk about who they'll be going to the upcoming festival with. There's someone Hazuki wants to go with, but that someone is already going with someone else. Meanwhile Kumiko somehow ends up going with you-know-who.

The audition for the competition participants has come. Everyone must demonstrate their abilities, whether they're a third-year or a first-year. And then, the results are revealed.

The band suspects Taki played favorites in choosing Reina in the auditions. Noticing the band's rising distrust of Taki and Reina, he makes a proposal.

Taki-sensei's proposal relieves the upset within the band, and everyone returns to practicing. Reina no longer isolates herself either, much to Kumiko's relief. But then she sees Yuko, who's been antagonizing Reina, speaking with her.

The competition's coming up. Kumiko is suddenly asked to play a difficult phrase from a different part. She begins practicing, but...

The competition performance is "only" 12 minutes long. It's both a blink of an eye and an eternity. The Concert Band members bet their entire youths on this competition. And Kitauji High School Concert Band's performance begins.