Guilt

In autumn 2017, Detective Tsutomu Godai and his partner, Detective Sergeant Nakamachi, investigate the stabbing death of Kensuke Shiraishi, a well-regarded Tokyo defense attorney found in the back seat of his abandoned car on a street in Minato Ward. Shiraishi's wallet is intact, but both his phones are missing. GPS data traces his final movements on October 31 to the Sumida River Terrace near the Kiyosu Bridge, where blood is found on his phone. The terrace was closed for construction, making it an isolated crime scene. Interviews with Shiraishi's wife, Ayako, daughter, Mirei, and colleagues yield nothing; all describe him as deeply moral with no enemies.

The investigation stalls until Godai discovers that Shiraishi visited the Monzen-Nakacho district several times before his death, spending hours at a café as though surveilling someone across the street. A phone call from a man named Tatsuro Kuraki to Shiraishi's office leads Godai to Kuraki's home in Anjo, Aichi Prefecture, where the 63-year-old retiree claims he merely sought legal advice and never met Shiraishi. Godai spots a votive slip and a car amulet, both from Tomioka Hachimangu Shrine, linking Kuraki to the area. Kuraki offers no alibi for October 31.

Godai interviews Kuraki's son, Kazuma, a young advertising executive in Tokyo, and suspects Kuraki has a woman in the city. The team traces Kuraki to Asunaro, a small restaurant in Monzen-Nakacho run by Yoko Asaba and her daughter, Orie Asaba, directly across from the café Shiraishi visited. Yoko confirms she gave Kuraki the shrine items and reveals that her husband, Junji Fukuma, was arrested as a suspect in a 1984 murder and hanged himself in his police cell while proclaiming his innocence.

The 1984 case involved Shozo Haitani, a financial adviser who scammed elderly victims, stabbed to death in his office near Higashi-Okazaki Station. Fukuma, one of Haitani's fraud victims, was arrested after being seen at the office but denied the stabbing and killed himself in custody. When Godai interviews the retired lead investigator, he discovers Kuraki's name in an old crime-scene notebook: Kuraki was one of two people who discovered Haitani's body.

Security camera footage places Kuraki meeting Shiraishi at a café on October 6, contradicting his denials. Confronted, Kuraki confesses: "I killed Shiraishi. And I also stabbed Shozo Haitani to death." In a detailed statement, he describes how Haitani extorted him after a traffic collision and how he stabbed Haitani, letting Fukuma take the blame. Consumed by guilt, he tracked down Fukuma's family, began visiting Asunaro, and decided to bequeath his estate to the Asabas. He claims he met Shiraishi by chance at a baseball game at the Tokyo Dome, consulted him about the bequest, and confided the 1984 murder. When Shiraishi pressured him to confess publicly, Kuraki killed him to protect his bond with the Asabas.

Despite the confession, Godai harbors doubts: No forensic evidence or footage corroborates Kuraki's account. Meanwhile, Kazuma's identity is exposed online, and his employer places him on leave. Kazuma begins his own investigation, unable to reconcile the confession with the gentle father he knows. Mirei Shiraishi also rejects the official narrative. She and Ayako retain Azusa Sakuma, a former prosecutor turned victims' advocate, to participate in the trial. Reading the prosecution file, Mirei insists her father would never have bullied anyone into confessing. She discovers that Kensuke had a tooth extracted the afternoon of the game and was told not to drink alcohol, making Kuraki's story of bonding over beer implausible.

Kazuma and Mirei meet by chance at the Sumida River Terrace, where Mirei has been leaving flowers, and discover they share the same conviction: Kuraki is lying. They begin sharing information. Kazuma finds that Tatsuro planned to move into his new house on May 15, 1988, the exact anniversary of the 1984 murder, reasoning no killer would choose that date for such a milestone. He also learns from Haitani's nephew, Masahiko Sakano, that Tatsuro appeared to have an alibi for the 1984 killing. With Godai's guidance, Kazuma visits a law firm in Nagoya and confirms that Tatsuro consulted a local lawyer about his estate over a year before supposedly meeting Shiraishi, proving he had no need for the lawyer's advice.

Mirei investigates her father's past and finds a childhood photo of Kensuke with an elderly woman in Tokoname, a pottery town in Aichi Prefecture. The woman is Hide Niimi, Kensuke's grandfather's first wife. A university friend reveals that Kensuke made secret trips to Nagoya during college, visiting someone "on behalf of his late father," and stopped in 1984. When Kazuma and Mirei travel to Tokoname, a neighbor confirms that Hide was defrauded by Haitani, the very man whose murder set everything in motion.

While Kazuma and Mirei investigate the past, Godai makes the critical breakthrough. Following Nakamachi's suggestion that the killer might have used a pay phone, Godai reviews security footage near the Kiyosu Bridge and identifies a caller at 6:40 PM on October 31: Tomoki Anzai, Orie's 14-year-old son and Fukuma's grandson. Godai presents this evidence to Tokyo Metropolitan Police Department leadership, arguing that Kuraki fabricated his confession to protect the boy. At Tomoki's home, the teenager immediately confesses.

With the charges dropped, Kuraki provides the true account. In 1984, he met Shiraishi, then a young law student trying to recover money Haitani had scammed from his grandmother, at Haitani's office. When Kuraki later discovered Haitani's body, he spotted Shiraishi climbing over the balcony railing. In a split-second decision, Kuraki nodded to him, closed the glass door, and wiped Shiraishi's fingerprints from the murder weapon. Weeks later, Shiraishi tearfully confessed that he had stabbed Haitani after the fraudster taunted him and threatened to call the police. Kuraki told the young man to focus on "the good of the living."

Decades later, Kuraki reconnected with Shiraishi, who began visiting Monzen-Nakacho to observe the Asabas from the café. Kuraki emailed Orie about Shiraishi using a private smartphone she had given him. Tomoki, who secretly read his mother's phone, discovered the message and tracked Shiraishi down. On October 31, Tomoki lured Shiraishi to the terrace and stabbed him. Shiraishi, mortally wounded, drove his car away and wiped the steering wheel to divert suspicion from the boy, his final act of atonement. When Orie realized what Tomoki had done, Kuraki confessed in his place, also claiming the 1984 murder to clear Fukuma's name.

The prosecutor's investigation reveals a disturbing dimension: Tomoki's claims of acting out of revenge for family suffering are largely fabricated. Under questioning, Tomoki admits he developed a fascination with murder after classmates feared rather than bullied him, and that learning Shiraishi's identity gave him a pretext to kill. Mirei tells Sakuma that she and Ayako will likely decline to participate in Tomoki's trial, accepting that her father's original crime was the root cause and believing Kensuke atoned through his final actions. She reflects that she and her mother have been transformed from the victim's family into the perpetrator's family.

A year and a half later, Kazuma visits Asunaro to tell Orie that Tatsuro has died of cancer, then follows a postcard to Mirei's new workplace at Sakuma's law office. He confesses his feelings. Mirei says she needs time, struggling with whether the child of a killer has "any right to exist," but promises to respond when she finds her answer.