Sound! Euphonium

is a Japanese novel by Ayano Takeda, published on December 5, 2013 by Takarajimasha. A manga adaptation illustrated by Hami began serialization on the Kono Manga ga Sugoi! Web website on November 28, 2014. An anime adaptation, produced by Kyoto Animation and directed by Tatsuya Ishihara, began airing in Japan in April 2015.

Two recap movies were aired respectively on April 23, 2016 and September 30, 2017. A spin-off movie entitled premiered in April 21, 2018.

Plot
Hibike! Euphonium begins when Kumiko Oumae, a girl who was in the brass band club in junior high school, visits her high school's brass band club as a first-year. Kumiko's classmates Hazuki and Sapphire decide to join the club, but Kumiko sees her old classmate Reina there and hesitates. She remembers an incident she had with Reina at a brass band club contest in junior high school.

Liz and the Blue Bird
The story focuses on Mizore Yoroizuka who plays the oboe, and Nozomi Kasaki who plays the flute in Kita Uji High School concert band. As they approach their senior year, this will be their last competition together in the selected piece “Liz and the Blue Bird” features a duet for the oboe and flute. As their final high school performance approaches, so becomes the growing rift stemmed between their ever-lasting friendship.

Official

 * Official Website (Japanese)
 * Manga Official Website (Japanese)
 * Anime Official Webiste (Japanese)

Other Sources

 * Wikipedia (English)
 * Wikipedia (Japanese)