The plot here involves Haruta and Chika who are members of their high school wind instrument club that is on the verge of being shut down because there are only four members. The two are childhood friends that got split up, but reunited nine years later and they spend their days studying and also trying to recruit new members. When a mysterious event occurs within their school, they band together in order to solve the mystery.
The series received an Animated Adaptation for the Winter 2016 Anime season by P. A. Works with character design by NamanikuATK of nitro+. It is licensed by Funimation for North America. After the anime ended, the adaptation continued in the form of two drama CDs that follows their adventures up until their graduation in 3rd year. The series also received a live Action adaption in 2017, including an original story that deviated from novel canon.
- Adaptational Sexuality: In the Live Action adaptation, Haruta and Chika's relationship develops romantically, despite Haruta being written as gay in the book and anime.
- Haru is constantly being kicked around by Chika, not to mention how his sisters treat him.
- Chika is constantly being mocked by Haru and everyone making fun of her being Book Dumb.
- The Chessmaster: A mild example, but Haruta pulls the strings behind every mystery to make the presentation of the solution look impressive in front of Kusakabe.
- Chick Magnet: Maren and Haruta. It's mentioned that several girls joined the brass club of because of them.
- Club Stub: While the Concert Band is in no danger of closing, in the beginning it has only 5 members.
- Drives Like Crazy: Haruta's sister Minami, who has a tendency to make sharp turns at intersections, as seen in episode 4.
- Dude Looks Like a Lady: Minor example, but after seeing him for the first time in so long, Chika initially mistakes Haruta for a girl.
- Evolving Credits: After the band gets more members the photo near the end of the opening changes to reflect that.
- Genius Ditz: Chika, in a way. The concert flute is a rather tough instrument for beginners, but she manages to get her playing to an acceptable level pretty quickly. Not that this gets acknowledged, though.
- Identical Twin ID Tag: The twins use different accessories in their hair.
- Irony: Chika left sports for music because she was bored about having to practice literally every day. In an attempt to impress Kusakabe-sensei she decides to practice everyday completely ignoring the fact that's why she left sports.
- Mistaken for Romance: The easy, affectionate (if slightly antagonistic) relationship between Haruta and Chika in the novel and anime is frequently mistaken as them being a couple, especially by their fellow band members, who seem to interpret it as Belligerent Sexual Tension.
- The Not-Love Interest: Haruta to Chika, at least in the novel and the anime. Despite looking like the candidates for a typical Childhood Friend Romance, they're both sincerely, if hopelessly, in love with their music teacher, Kusakabe.
- School Club Stories: The story partly surrounds around the concert band.
- The Unseen: Haruta has three sisters. Minami, the oldest, is the only one of them who gets any screen time. The other two, Tsugumi and Fuynua, are simply mentioned.
- You Gotta Have Blue Hair: Chika has bluish-grey hair, Naoko has green hair, Kaiyu has light green hair, and Maren has dark blue hair.