With the ensemble contest behind them, the members of the Kitauji High School concert band now aim to win a gold medal at the national competition. For third-year club president Kumiko Oumae and her friends, it is their last chance before graduation. Filled with anticipation and anxiety, Kumiko worries if she can successfully lead the band.

Amid her struggles, Kumiko encounters transfer student Mayu Kuroe. From her gentle demeanor to her talented euphonium skills, Mayu was a member of the Seira Girls' School concert band—a regular at nationals. While Mayu is friendly, Kumiko cannot help but have an indescribable feeling from their meeting.

As new members arrive and plans are set in motion, the club, with an insatiable hunger for a gold medal, learns what it truly takes to propel themselves to reach the national level.