The episode opens with a sunrise and the voice of Tomitake Jirō protesting that Takano Miyo would never execute the "Emergency Manual" on purpose. Rika reminds him that Irie has said the same thing, but since Takano knows her research will end in three years, Rika feels she will become desperate. Rika addresses both of them on the steps outside of the Furude Shrine. Irie agrees and notes that Takano's appeal failed. Rika explains that if the Emergency Manual is executed, "someone is going to be held responsible," and someone is trying to take down a rival. She tells Jirō that the Yamainu will murder him. Jirō laughs it off, but Ōishi Kuraudo arrives to tell him to take Rika's predictions seriously since she predicted the chain of murders five years prior. He then tells Rika he has brought someone who wishes to meet her. Akasaka Mamoru appears and suggests that Rika will not tell him to go back to Tōkyō again. In tears, Rika hugs him and repeats his name. Akasaka explains to them who he is and vows to her that it is his time to repay her for saving his wife.
Akasaka explains the "Alphabet Project" which consists of a source of illicit money his team investigated for years. Each year, it transferred a great sum of money to the Irie Institution. Irie protests that, "Tokyo" aside, his group merely seeks a cure for Hinamizawa Syndrome. When Jirō directly asks Rika how she learned all of this information, she answers that she is the heir to the Furude Shrine and has Oyashiro-sama with her, then looks away embarrassed. Jirō accepts that answer "for now" to Rika's surprise. Since they will have to wait for Jirō to find evidence, Rika asks Ōishi if he could find a reason to take Takano into custody. Ōishi muses he may lose his retirement allowance, but will do it if it is necessary. Irie reminds him that the Yamainu probably have spies in the Okinomiya Police Station. Akasaka suggests that Ōishi withdraw from the case given the risk to his retirement and Jirō agrees. Ōishi tries to laugh off being "lectured by youngsters"; however, he feels his biggest risk is to lose the ability to search for those who killed the Construction Manager. Rika replies that the true culprit behind all of the murders is not the Sonozaki family.
In the Sonozaki home Keiichi reacts with shock to learning the truth about Rika. Satoko confesses that when Rika revealed the truth the previous night, she, Mion, and Rena were shocked, but Mion affirms that they knew she was serious. Hanyū sadly reports that Rika has been constantly apologizing. A smiling Satoko breaks the tension by suggesting it would have been ruder for Rika to have kept her situation a secret. Keiichi picks up on this and proclaims that everyone must be secretly excited: Satoko has been waiting for an excuse to use her traps without holding back. Rena can "pull off some dangerous stunts," and she reminds him that he can crush Fate no matter how hopeless it may be. Hanyū suggests that if he is a "red, burning flame," then Rena is a "blue, gentle flame." Keiichi then turns to Hanyū and notes that although she is a recent transfer, she already understands them all.
A chibi Hanyū "Auu~! Auu~!"s in response to the flattery. Keiichi proclaims that it is their festival, and they will set off spectacular fireworks. Listening to this, Rika says in her Adult Voice to Hanyū that she is happy, since she never imagined everyone would believe her. Over quick flashbacks to Keiichi bludgeoning Mion and Rena, Shion stabbing Keiichi, Shion's insanity, and finally to all of them pledging to help Rena, then all pledging to work together from the end of Minagoroshi-hen, Hanyū explains that even if they do not clearly remember these past events all of the past events remain somewhere in their minds. Rika agrees that perhaps all of their experiences were not in vain.
In the Irie Clinic, Irie asks Takano over tea if she intends to continue the research after the Irie Institution closes. She asks him why he asks, and he nervously responds that he is uncertain of his future position. She admits that private research will prove difficult as it was with her "grandfather." She seeks to complete his research and have it recognized, but once the Institute and its research shuts down the work will become "shrouded in darkness" and her wish will not be fulfilled. She then laughs.
In the Sonozaki home Mion reviews the plan: Rika, Satoko, and Hanyū will hide in the Sonozaki home while Akasaka will stay in their house to give the impression they still live there. Mion notes that the most important role is Jirō's, as the scene shifts to a hotel in Okinomiya, since he must find evidence. As Rika explains over the scene of Jirō doodling the connection between "Tokyo," "Takano," and "Okonogi" with the numbers "03-671-2" underneath on a hotel stationary pad while talking on the phone, if he can find the evidence he can call in a stronger special forces, Banken unit to stop the Yamainu.
Mion reminds everyone of the theory that within 48 hours of Rika's death the Hinamizawa Syndrome will effect everyone. Rena adds that if Takano and the Yamainu cannot kill Rika, they cannot institute the Emergency Manual. Upon hearing this, Satoko leaps up and claims she knows the enemy's weakness and Keiichi exclaims that he understands it as well: Rika just has to die. As Satoko and Keiichi chortle in triumph, the rest watch them in stunned in confusion.
Irie knocks on the door of Satoko and Rika's home loudly asking for Satoko, Rika, and Hanyū and announcing himself as their "Master" arriving for their checkup. Akasaka answers, and Irie whispers that he is alone. Akasaka responds that there is evidence the home is being watched. He brings Akasaka provisions and the two workout a system of signals should an emergency occur since the phone is probably tapped. If Irie lets the phone ring one minute then hangs up, it means danger and Akasaka should escape. If it rings longer that means that Irie cannot contact him and Akasaka should immediately go to the Sonozaki home.
In Sonozaki's home, Ōishi expresses surprise that he should pretend Rika is dead, and Keiichi explains to him that if they pretend Rika has been dead for 48 hours, the failure of the Hinamizawa Syndrome to affect the people will undermine the excuse to proceed with the massacre. Ōishi agrees this will throw Takano's people into a panic. When Hanyū and Rika explains that they need his assistance to have the police officially announce they have found Rika's body Ōishi muses he must prepare himself for the consequences, and Hanyū replies that he does not have to agree to the plan if he does not want to. Ōishi laughs and states that if a "youngster" tells him that he cannot refuse.
He continues that he cannot give them an answer immediately since it will involve his colleagues. Hanyū excitedly explains that he should not worry because if he loses his retirement, Mion will make arrangements for him. Mion startles and Rika lets out a happy "Miiiii! It's the least you can do" for Ōishi's assistance. Hanyū and Rika agree with a "neee!" and a hysterical chibi Mion reacts to the sudden financial obligation. Ōishi admits he has no chance against them.
Jirō listens on the phone in his hotel room. The voice tells him that there are "some obscured sections in the Irie Institution," which the "Investigation Bureau" is now investigating. The voice also mentions the close relationship between the Late Koizumi and Takano, which probably explains Koizumi's efforts to establish the Irie Institute. The voice notes that Takano may have received "one billion yen" which would be more than enough to bribe the Yamainu. Jirō is shocked by this amount, and the voice admits that this suggests Takano is involved in some sort of conspiracy.
At the Furude Shrine during the preparations for the coming Watanagashi Festival, the voice of an old woman states that she heard that Rika has been ill. Irie finds himself questioned by three older women who also note that Satoko has also been staying at home. Surprised, he asks about their concern over Satoko given how her family was hated by the village. One of the women admits that perhaps the family was, while another states she does not want to see any child suffer. Sonozaki Oryō arrives with Kimiyoshi Kiichirō and asks Irie if Rika will be well enough to perform the ritual dance. She playfully admonishes him to "patch her up" before the Watanagashi Festival, but then she adds that she does not merely speak for Rika but for "that Hanyū girl as well," "and Satoko, too." Irie and the old women seem surprised, but Kimiyoshi explains he just talked with Oryō and she agrees they should not cling to the past "curses, grudges, and whatnot." Oryō affirms that it is the job of the elderly of a village to care about all of their children. A happy Irie proclaims that Satoko will be happy to hear that.
Late in the same day, Ōishi visits the grave of the manager of the dam construction project.
He asks if the deceased laughs since it turns out that the Sonozaki family had nothing to do with his death. He continues that he has come every year promising to arrest Oryō. Now, he is "about to cross a dangerous bridge." While the result may not balance the risk, he might learn the truth behind the murders. He is surprised by Shion and her mother Akane bearing offerings. Akane states it is the first time they have met at the grave. Ōishi notices that she carries the hydrangea that he has found placed at the grave every year. Shion states that she carries ohagi made by her grandmother, Oryō. Surprised, Ōishi asks why, since the deceased had such a bad relationship with the Sonozaki family, they would do this. Akane explains that after a kendō or rugby match, there are no allies or foes. Children will take over Hinamizawa, and the adults must end the dam war for their sake. Ōishi agrees that there are "great youngsters" living in Hinamizawa, and he has made his resolution. Addressing the deceased, he declares himself a detective who will do his part in "Mion-san and Keiichi-san's festival."
The end titles cease with the pathologist slamming his beer bottle on the table in the traditional restaurant and announcing that he will join Ōishi's plan. Ōishi wonders how he can decide so quickly only to have his subordinate Kumagai Katsuya announce that he will join as well. Kumagai cites meeting Akasaka as inspiration: "I'm a policeman, and as a policeman, I want to fight evil!" Inwardly, Ōishi calls for the raising of the curtain on the festival.
Chibi Rika asks Chibi Hanyū if she has heard of oyashirosama.com:
- Chibi Hanyū: Au! Au! It's one of my favorite sites! It's just filled with all kinds of "Aahaaah!" and "Ohhooo!" content!
- Chibi Rika: Miii!
- Chibi Hanyū: If it has one flaw, it would be that it's hard to find the entrance, but other than that, you could spend your entire weekend just downloading videos and seeking out new encounters!
- Chibi Rika: No! That's the wrong site!
Chibi Hanyū insists that "Browsing sites in the middle of the night is a pleasure reserved for adults!" as Chibi Rika protests "Mii! Mii! Mii!" When Chibi Hanyū introduces the next episode and encourages viewers to watch it, Chibi Rika muses in her Adult Voice: "even though it is something children should not watch."
In order of appearance.
- Tomitake Jirō
- Furude Rika
- Irie Kyōsuke
- Ōishi Kuraudo
- Akasaka Mamoru
- Akasaka Yukie (mentioned)
- Construction Manager (mentioned)
- Maebara Keiichi
- Hōjō Satoko
- Ryūgū Rena
- Sonozaki Mion
- Furude Hanyū
- Takano Miyo
- Takano Hifumi (mentioned)
- Tetsurō Okonogi
- Koizumi (mentioned)
- Sonozaki Oryō
- Kimiyoshi Kiichirō
- Sonozaki Akane
- Sonozaki Shion
- Old Man from Forensics
- Kumagai Katsuya
- In previous lives if Akasaka returns to his wife, he prevents her fall to her death. He then either fails to return five years later to help Rika or does so ineffectively.
- In previous lives, Jirō never takes Rika's warnings seriously.
- Akasaka recalls Irie from Sign of Himatsubushi-hen.
- Keiichi has a flashback to his killing of Rena and Mion depicted in Chapters One and Four of Onikakushi-hen.
- Flashback to Shion stabbing Keiichi in Wish of Watanagashi-hen.
- Flashback to Shion's insanity in Watanagashi-hen.
- Flashback to pledge to help Rena in A Home to Return To of Tsumihoroboshi-hen.
- Flashback to all pledging to work together from the end of Finale of Minagoroshi-hen.
- Ōishi has acted on the belief that the Sonozaki are behind the death of his friend, the Construction Manager, and the series of mysterious deaths.
- Ōishi plans to make a vegetable garden and take up ballroom dancing in Hokkaido after retirement.
- "Banken" means "watchdog," while the Yamainu literally means "mountain dog."
- When Irie claims that Rika, Hanyū, and Satoko's "Master" has arrived he says ご主人様 (goshūjin-sama) "your husband."
- "One billion yen" is ~$4,255,320 in May, 1983 or ~$10,748,345.37 in 2018.
- Rika reveals the truth to her friends.
- Ōishi talks with Hanyū.
- Oryō has noticed Hanyū and demands that Irie care for all of the children, including Satoko.
- Ōishi encounters Akane and Shion making an offering at the grave of the manager of the dam project.
- "We ought to take what she says very seriously. After all, she is the girl who five years ago predicted the series of mysterious deaths in Hinamizawa." – Ōishi
- "This is the first time you've ever taken what I said seriously." – Rika to Jirō
- "We don't mean to use you as a steppingstone towards victory." – Hanyū to Ōishi
- "The dam war is long over, if a kid of the village catches a cold, it's the job of the elderly to worry about them." – Oryō
- "Browsing sites in the middle of the night is a pleasure reserved for adults!" – Chibi Hanyū