While she is crying, she imagines a fairy egg that curses her by sealing her words, so she won't hurt people again.

Years later, when Jun is attending high school, her homeroom teacher, Kazuki Jōshima, signs her up as a member of the Community Outreach Event along with three other classmates: When she goes to the committee's room to reject her position, Jun hears Takumi singing and is captivated.

Her class decides to perform a musical for their school festival based on the story of her experience narrated in the form of a fairy tale.

Heartbroken, she runs away and meets the fairy egg, who reveals that she has worsened the curse by trying to convey her feelings for Takumi.

Jun doesn't show up on the day of the musical, leaving Natsuki to fill her role while Takumi frantically goes searching for her.

Wanting to hear her voice once more, Takumi allows Jun to lash out all of her anger and frustration until she is satisfied.

As the musical ends, Jun realizes that the fairy egg was actually nothing but imagination that she created to have someone she could blame for her condition, and now she decides to open up her heart, coming to terms with her past.

As the movie ends, Takumi and Natsuki reconcile their relationship, while Daiki finally confesses his feelings to Jun.

[5] The film's main theme song is "Ima, Hanashitai Dareka ga Iru" (今、話したい誰かがいる) performed by Nogizaka46.

The site's critics consensus reads, "Anthem of the Heart is an excellent anime, whose truly captivating story will satisfy anyone who will succumb to it".

[22] Directed by Naoto Kumzawa, it stars Kyoko Yoshine, Kento Nakajima, Anna Ishii, and Ichiro Kan.