Detective Conan: Full Score of Fear

The film opens on the stage of a concert hall during a rehearsal, where a woman observes two men. She quickly sends a message on her cellphone, and moments later an explosion rips through the hall. The blast kicks off a mystery as investigators begin to piece together what happened.

Elsewhere, a mysterious figure watches the news on a computer and speaks of getting closer to a plan called 'Silent Night'. The silhouette hints at a larger scheme driving the events to come. The motive remains shrouded as the plot tightens its grip.

Conan Edogawa talks to Ran Mori on the phone while attempting to understand the explosion aftermath. He spots an old man picking a piano key from the wreckage and pocketing it before driving away. Ran invites him to a rehearsal at the soon-to-open hall, but he declines and accuses her of meddling.

At the rehearsal for the hall's opening, Kogoro Mori, Ran, Sonoko, and the Detective Boys meet the performers: Kazuki Domoto, Takumi Fuwa, Hans Müller, Genya Domoto, Rara Chigusa, Shion Yuhane, and Reiko Akiba. The kids ask Akiba to help the school choir sing the anthem, but she urges them to leave so Shion can perform without fear. The mood is busy and tense as preparations begin.

The next day, Ran plays the piano while the Teitan Elementary School choir sings their anthem. Akiba comments on each child’s performance while Conan is notably off-key, despite having perfect pitch. Genta's antics and the classmates' observations set the stage for the coming tension.

At the hospital, the doctor tells Genta that his throat is severely inflamed by chemicals, and he won’t be able to speak for about four days. The Detective Boys, Sonoko, and Akiba accompany him home, and a chase with a truck nearly ends badly. Akiba’s quick thinking saves them, but the culprit escapes.

Two murders shock the group: Osamu Shida dies in an explosion with only the flute's foot joint left at the scene, and another victim plunges from a paraglider after being cut, with the flute's headjoint found in the victim's car. The deceased were former members of a group called the Quarter Quintet. The crimes link a shared past to the current threat.

Conan, indebted to Akiba for a reason he has forgotten, follows her to a forest where he often relaxes before the concert. An assailant wounds her leg with a gun and she is briefly attacked; they escape when the shooter pauses. They press toward safety as danger closes in.

Mori incorrectly deduces that Genya Domoto is the killer because of a past drunken performance of Beethoven. Genya reveals his hair is natural and that it was inherited from his mother, debunking Mori’s theory. The tension shifts as truth conflicts with assumption.

Back at Domoto Hall, preparations for the concert continue and Sonoko notes a balcony with reserved seating, including one for Shinichi. Conan and Akiba search for Kazuki to report that the organ key is slightly flat, hoping to fix it before showtime. The minor issue becomes a potential risk if ignored.

Near a lake, Akiba and Conan are knocked out by the assailant with a wrench. They wake downstream and hear an explosion coming from Domoto Hall, confirming the danger is real and ongoing. Conan uses his understanding of sound to discuss how phones work and how to alert the authorities.

Conan enters the balcony and reveals Takumi Fuwa as the killer, driven by losses and pride. Akiba tries to stop the explosions by singing Amazing Grace in F major, which bypasses the triggering notes. Officer Sato fires and foils Fuwa's suicide, and Kazuki explains his past actions to spare his friend’s pride.

Outside the hall, Ran hears Amazing Grace played on a violin and goes into the woods. Conan explains that Shinichi played the tune to be forgiven, and Ran accepts the gesture. The moment ties back to the emotional core of their relationship.

Akiba reveals that Amazing Grace is a song of forgiveness and sings it by the river on the anniversary of her fiancé’s death. Conan is seen at home, playing Amazing Grace in the library to examine the 'strange habit' Shinichi has when he plays, connecting the case to his double life.