Old train schedule

The old train timetable among Kyoichiro Kaga’s mother’s effects is both a personal remnant and a forensic map. Fingerprints connect it to Mutsuo Koshikawa, while the sections repeatedly handled direct the investigation beyond Ishinomaki to Onagawa—the last stop on the Ishinomaki Line and the location associated with the nuclear power plant. The timetable’s significance lies in how ordinary use, preserved on paper, gives investigators a concrete path into the hidden life of Shunichi Watabe.

Provenance and Forensic Examination

The timetable was almost twenty years old when Shuhei Matsumiya noticed it on Kobayashi’s desk. Kobayashi explained that Kaga, of Nihonbashi Precinct, had provided it: the book had been among his mother’s effects, and Kaga had obtained a second copy for the task force while forensics examined the original. The age of the object set it apart from an ordinary investigative document; it had belonged to Kaga’s mother before becoming evidence in a case that would connect her past to Watabe.

Forensic examination first established a direct link. Investigators recovered several fingerprints from the timetable that matched prints found in Mutsuo Koshikawa’s apartment. Their number and placement suggested that Watabe, rather than Kaga’s mother, had used the book most. Because Koshikawa and Watabe were the same person, the prints supplied objective physical evidence connecting the man who had lived under the name Watabe in Sendai with the person known as Koshikawa.

The investigators did not stop at identifying whose hands had touched the book. Forensics dusted every page, and the recovered prints clustered in particular sections. A photograph made with a special light source and filter made the marks visible on a darkened spread; the location and concentration of the prints could then be read alongside the timetable’s routes. The book thus offered more than a general association: its pattern of use preserved clues about where Watabe had been trying to go.

The Route Toward Onagawa

One heavily handled spread gave the timetable for the Sendai Line, which runs from Sendai to Ishinomaki. The prints were especially concentrated around Ishinomaki Station. At first, Matsumiya wondered whether that meant Watabe regularly traveled between Sendai and Ishinomaki. Kaga corrected the assumption behind that inference: touching a station name on a printed timetable did not establish that it was the traveler’s final destination, since he might have changed trains there and continued onward.

A separate cluster on the page for the Ishinomaki Line sharpened the route. That line runs between Kogota and Onagawa, and the marks led investigators to Onagawa Station. Because Onagawa was the line’s last stop, with nowhere farther to travel on that route, Kobayashi reasoned that it was likely Watabe’s final destination. Kaga supplied the crucial association: Onagawa meant the nuclear power plant. The timetable therefore redirected attention from Ishinomaki as an apparent endpoint to the destination beyond it that the rail connection made accessible.

A Private Object in the Investigation

The timetable’s evidentiary force depends on the distinction between ownership and use. It came from Kaga’s mother’s belongings, but the distribution of prints suggested that Watabe had handled it more extensively than she had. The book consequently brought Kaga’s family history into contact with the investigation without making the timetable merely a keepsake: its physical traces helped identify the user and recover a route associated with his concealed life.

That route mattered in a wider effort to understand Watabe’s connection to Hiromi Asai and the people around her. Kaga argued that Watabe and Hiromi had been connected for at least ten years, and that Hiromi may have supported him financially. Given Watabe’s estimated age, his disappearance, and his acquaintance with Michiko Oshitani, Kaga concluded that the most plausible identity was Hiromi’s father, Tadao Asai. The timetable does not establish that identity on its own, but its fingerprints help substantiate the link between Watabe and Koshikawa, while its station marks reveal a line of inquiry into Watabe’s movements.

Narrative Significance

The timetable turns routine consultation into durable evidence. Its pages were made to guide a traveler through scheduled routes; years later, the pressure of a finger, preserved as a forensic trace, allows investigators to reconstruct which parts of the route mattered to the person using it. A seeming endpoint proves incomplete: Ishinomaki is not the conclusion, because another line carries the investigation onward to Onagawa.

Its appearance also bridges two strands of the story. As an object recovered from Kaga’s mother’s effects, it belongs to the personal history he is trying to understand; as a source of matching prints and route-specific clues, it advances the police inquiry. The result is a quiet but decisive reversal in the timetable’s role: once a practical guide for its user, it becomes a record that speaks to investigators about both his identity and where he may have been headed.