Himatsubushi-hen

Himatsubushi-hen (綿流し編) is the fourth arc in the series and the final arc of the original  visual novel. It is told from the perspective of Mamoru Akasaka and follows his investigation into the kidnapping of the grandson of a government official.

Plot
Himatsubushi-hen follows Detective Mamoru Akasaka from the Metropolitan Police Department in Tokyo and takes place five years prior to any of the previous arcs. Mamoru's wife Yukie has become pregnant with their firstborn. Unfortunately, Mamoru can't be present for the birth as he is being sent to Hinamizawa on an investigation into the kidnapping of Toshiki Inugai, the grandson of the Minister of Construction. Upon arriving in Hinamizawa, Mamoru is greeted by Rika Furude at the bus stop. Rika shows Mamoru around the village and, along the way, they meet Kuraudo Ooishi, a detective from Okinomiya who helps Mamoru with his investigation. Rika then takes Mamoru to the Furude Shrine. Rika adopts a serious tone and warns Mamoru to return to Tokyo immediately or he will regret it. Mamoru, though frightened by this change in Rika, ignores her warning.

Mamoru later meets up with Ooishi and plays a game of mahjongg with him and the dam construction site manager. After being impressed by Mamoru's mahjongg skills, Ooishi introduces Mamoru to "Mr. Satou", an informant who tells Mamoru about secret family meetings within Hinamizawa. Specifically, the informant mentions that Oryou Sonozaki, the head of the Sonozaki family, knows about the kidnapping of the Minister's grandson, information which was supposed to be top secret. The informant also reveals that Oryou knows that a newcomer from the public security sector would be visiting Hinamizawa to investigate, referring directly to Mamoru. This leads Mamoru to develop a degree of fear while in Hinamizawa, which he describes as "enemy territory."

The next day, Ooishi shows Mamoru a new piece of evidence, a wallet belonging to Toshiki Inugai. This new evidence confirms Mamoru's suspicions that the Onigafuchi Guardians, a dam resistance group base din Hinamizawa, are behind the kidnapping. Ooishi and Mamoru drive to the remote village of Takatsudo in pursuit of Toshiki. Along the way, they pass the dam construction site, which is surrounded by protesters. Among them is Rika, who stares blankly at Mamoru as they drive past.

Meanwhile, Toshiki Inugai struggles to think of a way to escape his captors and eventually decides to fake illness in order to get a doctor to check on him. The kidnappers call Kyousuke Irie to the hiding spot in Takatsudo to examine Toshiki. After determining that Toshiki needed to be taken back to the Irie Clinic, the kidnappers stopped Irie and sent him back to the clinic without Toshiki.

As Ooishi and Mamoru enter Takatsudo, they pass by Irie, who is driving the opposite direction. Suspicious, Ooishi checks his map and determines that the kidnappers must be close by. Mamoru and Ooishi find the kidnappers and Toshiki in an abandoned hut and get into a fight with the kidnappers that leaves Mamoru with a fractured skull and bullet wound in his shoulder. The kidnappers escape, however Toshiki is rescued. Mamoru wakes up in Irie Clinic, where he is advised to stay in rest for 24 hours. Ignoring this advice, Mamoru goes to the clinic lobby in search of a phone with which to call Yukie, only to discover that the hospital phone and the nearby public phone have both had their cords slashed. While searching for a different public phone, Mamoru runs into Rika, who talks him out of searching for the phone seeing as calling hours for the hospital Yukie is staying at are now over. Mamoru joins Rika at the Watanagashi Festival that is occurring at the Furude Shrine, which currently is mostly just a gathering of a small number of people for drinks. Rika reveals several truths about the future to Mamoru: she predicts that the Festival will become large and wonderous but that a grisly murder will coincide with the Festival every year until 1983, when Rika herself will die. She details the the dam construction site murder, the dam supporters' accident, the priest's death, and the murder of the housewife and then confides in Mamoru that, depsite her fate, she doesn't want to die. Mamoru returns to the clinic feeling very confused.

The next morning, Mamoru receives a call and learns that Yukie had died the night prior in an accident walking down a flight of stairs. Devastated, and having finally understood Rika's warning, Mamoru immediately returns to Tokyo.

The story picks up seven years later, in 1985. Mamoru meets up with Ooishi to discuss the Great Hinamizawa Disaster. In the seven years since Mamoru left, everything that Rika predicted, including her own death, came exactly true. Mamoru tells Ooishi about Rika's predictions, inspiring Ooishi to further investigate the cold cases of the now closed Hinamizawa. Mamoru and Ooishi ultimately never solve the case, however, they do end up writing a book about the murders and their investigation entitled Higurashi no Naku Koro ni.

Villagers

 * Rika Furude
 * Mion Sonozaki
 * Oryou Sonozaki
 * Kiichirou Kimiyoshi
 * Mr. Furude
 * Mrs. Furude
 * Kyousuke Irie
 * Makino

Outsiders

 * Akasaka Mamoru
 * Ooishi Kuraudo
 * Minister Inugai
 * Toshiki Inugai
 * "Mr. Satou"
 * Dam construction manager

Mentioned

 * Yukie Akasaka
 * Hondaya
 * Jirou Tomitake
 * Miyo Takano
 * Mr. Houjou
 * Mrs. Houjou
 * Aunt Houjou

Deaths and Disappearances
All deaths and disappearances are listed only as they are told in Himatsubushi-hen and apply only for the individual arc, not the overall series.

Deaths

 * Yukie Akasaka, fell down the stairs of a hospital on the night of Watanagashi, June 1978, while coming down from the roof.
 * Everyone Rika predicted would die, on the Watanagashi Festival from June 1979 to June 1982.
 * Jirou Tomitake, died of blood loss after clawing out his own throat June 19, 1983 on the night of the Watanagashi.
 * Miyo Takano, killed and burned in an oil drum in the Gifu Mountains June 19, 1983 on the night of the Watanagashi.
 * Kyousuke Irie, committed suicide June 21, 1983 with sleeping pills in the clinic.
 * Rika Furude, found drugged and disemboweled June 21, 1983 in front of the Furude shrine.
 * Everyone in Hinamizawa not listed otherwise, died June 21-22 1983 of gas poisoning during Great Hinamizawa Disaster.

Disappearances

 * Katsuya Kumagai, went missing June 20, 1983 during an investigation.