In the wake of a terrorist attack at the Tsuruga Nuclear Power Plant, Japan quickly passes a sweeping anti-terrorism bill that broadens the reach of the Media Betterment Committee (MBC) and other agencies. On a date, Iku Kasahara and Atsushi Dojo are recalled to the Kanto Library Base to guard Kuroudo Touma, the author of Nuclear Peril who has become a wanted target for the MBC. After purchasing eyewear to help with Touma’s disguise, Kasahara and Dojo cross paths with Kiyoka Kojima, a bookstore staff member who was saved by Dojo in a past incident. The Library Defense Force (LDF) then files a lawsuit, with Touma as the plaintiff, against the MBC at the Tokyo District Court. The court rules in Touma’s favor, prompting an appeal to a higher court.
One night, members of the Future Library Committee attempt to abduct Touma but are quickly stopped by Mikihisa Komaki and Hikaru Tezuka. Asako Shibasaki tells Hikaru that she will handle his brother Satoshi. Touma is moved from the Kanto Library Base to Kazuichi Inamine’s estate. Meanwhile, Shibasaki proposes to Satoshi to become the voice of anti-censorship in the National Diet in exchange for overlooking his abducting plot. A few days before the high court’s verdict on the appeal, MBC agents infiltrate Inamine’s estate, but Kasahara and Dojo manage to bring Touma back to the Kanto Library Base. On the day of the verdict, the high court rules in favor of the appeal, and the case proceeds to the Supreme Court of Japan.
During a strategy meeting, Kasahara suggests Touma seek asylum, which the LDF approves as a last resort if they fail to win in court. On the day of the verdict, the Supreme Court rules that Touma is prohibited from writing for five years. Kasahara, Dojo, and other LDF members race to move Touma to a safe asylum destination, but they are blocked by MBC forces. Dojo is shot in the leg and taken to Kiyoka Kojima’s Books Kinokuniya store to recover, while Kasahara and Touma press on toward the consulates in Osaka. Along the way, Touma reveals his plan to craft a fairy tale about a troubadour saved by two bluebirds from oppression, a story meant to inspire music even if it is not approved by any king.
The pursuit reaches near the British Consulate-General, where they are momentarily halted by MBC reinforcements. The LDF arrives to provide cover, and the two finally reach the American embassy, where a British diplomat intervenes to grant asylum after a call from the LDF. The incident draws international attention and condemnation of the Media Betterment Act. A week later, Kasahara visits Dojo in hospital, and the two reaffirm their love. A year later, with the act revised to prohibit the use of weapons, Kasahara, now married to Dojo, oversees new LDF recruits as their instructor.
