In the school staff office, Mion explains to Chie as Chie closes a window window to due to the sounds of insects, that because there is no air conditioning in the classroom they cannot close the windows. Chie assures her that Principle Kaieda is calling the Forestry Service, and that they will arrive quickly. She tells Mion that she thinks "the smell" could come from the products they use, and that she will asks them to attend to it. Mion says she understands and starts to leave. The phone in the office rings, and Chie answer.png.pngs the phone and says, "Ryūgū-san? Where are you right now?" Mion stops. Chie says she understands and she will be right there. She then hangs up.

Rena's boots walk along the wooden flooring.

In the classroom, Keiichi responds to Mion's news that Rena called while Rika listens. Mion explains that Chie has gone to meet her. Two of the unnamed young girls run laughing past them, then out the door where they stop before Rena who is holding her axe. Inside, Mion, Keiichi, Rika, and others are startled by the young girls' screams. They turn to see that Rena has her axe at the throat of one of the girls. Rena commands everyone to stand and gather at the center of the classroom. Rena ignores Keiichi's protests and directs Mion, as the class representative, to make the students comply.

When Mion asks her what she is doing, Rena slams her axe into the teacher's desk.

A number of police and their cars are gathered outside the school. Kumagai Katsuya's voice explains that at around 1 P.M. a student entered the Hinamizawa School within the Forest Service and took a classroom hostage, and then instructs all available officers to go to the school. Ōishi stands smoking next to Kumagai who reads from his notebook. Behind them stand Chie and Kaieda. Komiyama talks on the police car radio through its window. Kumagai continues to explain that it is not known if Rena has accomplices. Further, since the curtains on the windows are closed, they cannot determine what is happening inside. As Ōishi asks about the Forest Service, Chie buries her face in her handkerchief and starts to cry, and Kaieda tries to console her. Kumagai continues that since the staff was not present, "only the 15 students" are hostages.

Komiyama interrupts them to tell Ōishi that they have a call from the suspect. He takes the call, and Rena asks him to confirm he is Ōishi. The scene moves through the otherwise deserted school to focus on students lying on the ground with their arms and legs tied by jump ropes. Ōishi promises that he is on her side and together they can expose the Sonozaki conspiracies. Rena informs him that at first Keiichi also did not believe her, but now he is also on her side. Ōishi asks if he can talk to their "new ally." After a long pause, Rena agrees.

After identifying himself to Keiichi, Ōishi asks him what Rena is doing at that moment. He responds that she is with the hostages. Rena walks amongst the frightened children. On the phone, Ōishi instructs Keiichi that if the answer.png.png to his question is "yes," Keiichi says, "はい (hai)," and if it is "no," he should say, "ええ (ee)." Keiichi admits that he does not know what Rena wants, is pretending to help her because she threatened him and that she is the only suspect. Rena interrupts the call to tell Ōishi this shows that Keiichi is on their side.

She tells Ōishi that it is now his turn. She reminds him of what he promised previously and asks him if his investigations of the Sonozakis have uncovered the research laboratory of the parasites. Ōishi stalls that various investigation units "are preparing a mass investigation." "You're too slow!" Rena barks. She harangues him for his slowness then demands to know if he really is on her side. Ōishi tries to stall a bit more by claiming they need "evidence." As she scratches at the bandages on her neck, Rena responds that she understands. A close-up suggests multitudes of little white worms squirming from wounds on her neck. Rena offers to give Ōishi Takano's scrapbooks. Some of the parasites fall at Rena's feet, she watches them start to squirm away. Ōishi offers to pick up the scrapbooks, but Rena looks up and darkly informs him that Keiichi will take them.

Keiichi slides open the school door. Ōishi formally introduces himself to Keiichi. Keiichi apologizes and explains that Rena instructed him not to speak to him and hands Ōishi the scrapbooks. Ōishi responds that he understands, then hands Keiichi an object. He tells Keiichi "it is fine," and explains that Rena cannot see them. Keiichi starts to ask what it is, but Ōishi instructs him to read it on the way back to the classroom. In the area with the shoe lockers, Keiichi looks at what Ōishi handed him. The note reveals he has a communication device and a short-range self-defense spray.

He returns to the class to find Rena pouring gasoline on the floor as the children whimper in fear. Satoko is one of them. She explains that it is "insurance in case of an emergency." Outside, Ōishi hears their conversation broadcast on a radio. A police officer runs up to Ōishi and reveals that one of the scrapbooks contained a note from Rena. The note reads: "I will probably claw at my throat and die tonight. So I'm setting 7:00 P.M. as the time limit for negotiation. If the mass investigation does not take place by 7:00 then I shall choose to burn to death with the hostages." Kumagai notes that it is just before 6:00 P.M. The note continues: "I have also prepared another way to set off the explosion. It's like a simple time bomb made from gas and a kitchen timer. I have also set that for 7:00. I hope you take action quickly. To my ally, Ōishi-san."

As that part of the note is read in Rena's voice, Rena pulls her axe from the teacher's desk. Outside, Ōishi crumples up the note and growls at being called her "ally." Back in the classroom, Rena raises her axe and brings the blunt side down on Mion's head. Keiichi screams at her to stop. Rena retorts that he promised not to move from the wall. She turns back to Mion and continues that she cannot forgive her for digging up the corpses and "betraying" her. As Mion looks down stoically, blood starts to flow down her face. Claiming that she trusted Mion, Rena rains blows down on her head.

Keiichi approaches again, begging Rena to stop, but she threatens to light her lighter. The phone rings. Rena answer.png.pngs and learns it is Ōishi. Keiichi looks sadly at Mion. He then feels the earpiece in his pocket and puts it in his left ear. Kumagai on the other end asks if Keiichi can hear him and instructs Keiichi to cough if he can. While Rena talks to Ōishi, Kumagai explains to Keiichi that Rena claimed that she set a timed explosive device set to go off at 7:00 P.M, or in about 15 minutes. Kumagai asks him to find the device and deactivate it. Kumagai expects that the device is plugged into an outlet, and he asks Keiichi if there is something plugged into the outlet in the classroom. When Keiichi informs him that no such advice exists in the classroom, Kumagai instructs him to search the other rooms of the building. When Keiichi protests that he cannot do this in fifteen minutes, Rika calls to him. Satoko slyly adds that traps are her specialty. Keiichi decides then to ask their foremost "trap expert" how she would blow up the room. Satoko responds that she will show Rena that her trap "is nonsense when I'm serious."

As the higurashi c ry, Rena barks into the phone that whatever Ōishi told her will not happen in time. As she rants, Satoko suggests to Keiichi that there must be a cord somewhere. Keiichi vows to find it, and Rena hears him talking. Keiichi asks her if she heard a strange sound. She looks at him suspiciously, then orders him to investigate. As he leaves, she reminds him that she does not want him to get her "mad." Keiichi tells her to trust him and begins his search. In one room, he finds a cord plugged in that runs under a door. He follows it through a few rooms until he finds the timer. Inspecting it, he realizes the cord is simply taped to the bottom. Rena appears behind him to sarcastically ask why he would have an alarm clock.

She notes she trusted him, he is "horrible," and she raises her axe with the sharp edge down. Before she can strike, Rika runs in and tackles Rena. Rena's lighter slides across the floor. He grabs it, then hears Satoko announce that she found the timer. Rika places herself between Keiichi and Rena and tells Keiichi to find Satoko. When Keiichi protests, Rika reveals that "this isn't the first time," and "If I had shown a bit more effort the last time, then. . . ." Keiichi hears Satoko plead that there is no time left. Keiichi apologizes to Rika and leaves. Rena starts laughing hysterically at Rika. She tells Rika that she will be killed, "By Rena, who's absolutely furious!" In her Adult Voice, Rika responds sternly, "I'll play with you."

In the hallway, Keiichi asks Satoko what she means. She explains that she recalled from the morning other children complaining about the smell. Another boy complained about how his baseball was missing and accused her of stealing it. Satoko explains that the smell was gasoline, and Rena used the ball to close the rain gutter and fill it with gasoline from the second-floor roof. This means that the timer is located on the roof. Keiichi pats Satoko on the head. As he leaves, Satoko tosses him a bat with the name "Satoshi" on it. As he runs away, Satoko says, "Nii-Nii."

As he runs, Keiichi calls to Ōishi to inform him that he has Rena's lighter, and the timer is located on the roof. Keiichi uses Satoshi's bat to smash a stuck window to gain access to the roof. Kumagai announces that there is less than one minute. Keiichi locates it and reaches "cancel" just before it goes off. As Keiichi declares, with one second left, that he made it in time, Ōishi orders his officers to enter the building as the children start to escape through a window. Satoko holds out her hand to help Mion though the window.

Kumagai receives a call from the fire department and informs Ōishi that the building remains dangerous given all of the vaporizing gasoline. Ōishi protests that Keiichi is still in the building as the scene shifts to him sitting on the roof as Rena appears with her axe. As she scratches at her neck, she tells Keiichi that she cannot believe he was able to find her detonator. Keiichi replies that it is over: "Game, set, and match!" Rena replies that she was doing her best to fight "the aliens," and if humanity perishes it is all his fault. He rhetorically asks who believes in aliens "nowadays." He calls her "stupid," which irritates her. He challenges that if she really wants him to believe her, then they should settle it like the Club does. Rena guesses his meaning: the winner is right.

The two clash and banter as expected in an anime. Keiichi claims that when she loses, Rena will become his personal maid. As they clash, Kumagai calls to Keiichi to jump to safety, but Keiichi ignores him. He complains to Ōishi who is lost in watching. The watching school children cheer for Keiichi. Meanwhile, holding her left arm, Rika emerges from the school and falls. The police dressed in riot gear rush to help her. Satoko and Mion see this and rush to help her as well. Back to the clash, Keiichi suggests to Rena that since the water gun fight she has wanted another such fight. Rena admits that she has. They renew the clash.

On the ground, Rika turns from Mion, looks to Rena and Keiichi clashing, and says, in her Adult Voice, that "Keiichi might be able to find an exit out of this tragic maze." Mion looks surprised at Rika's remarks. As Keiichi and Rena lock bat and axe, Keiichi reminds her of her punishment when she loses. Rena asks him if the maid uniform she will wear will be "cute." Keiichi pushes her away as he asks her what is her punishment for him if she wins. She stands surprised. Keiichi continues that if she wins he will believe her story: "I'll believe that aliens control the world." Rena pauses then replies that it is not fun if she wins. She smiles and claims that she wants the same reward as Keiichi's. Keiichi protests that he will not be a maid; Rena replies that he does not have to be a maid, "but the rest is the same." She wants him to greet her in the morning and say goodbye to her at night. Further, whoever wins, they will always be together. Keiichi happily agrees, though "the treatment will be different!"

Rena laughs. After they both admit their fight has been fun, the two charge with all of the drama expected in such scenes. After a clang, Satoshi's bat flies in the air. Rena sits on Keiichi with her axe raised. Keiichi compliments her on being "good." Rena observes that the fight is over. Keiichi notes that it is not until she brings her axe down. Rena admits meekly that she does not want to. Tears then flow from her eyes and she yells that she does not want to. She asks why things ended up like this. She wonders why, when she tried to believe in everyone, she could not believe in Keiichi. She lowers her axe, and Keiichi asks her if she is able to understand. Still crying, Rena asks why she wrecked the days that were fun. Keiichi calls her "amazing" for realizing her "mistake."

Rena sits next to him and reminds that she hurt her friends, including "terrible things" to Mion. Keiichi happily tells Rena to apologize to Mion later, then observes, "I think it's a good scar for me to tell the sisters apart." He embraces Rena and reminds her that she consults with her friends. Crying, she embraces him as well. Ōishi and the officers, the school children, and Mion and Satoko watch in awe. As for Rika, tears start to fall as the higurashi c ry.

as the First Season end-title song "Why, or Why Not" starts, the cards of the rope, gun firing, syringe, and bottle of poison appear on a table while Keiichi complains that Satoko is good. A chibi Satoko laughs as the rest sit chibi frustrated. Satoko gloats that Keiichi is "a hundred thousand years too early" to win again here. Returning to normal, Rika observes that if Satoko is serious, she will have to be serious as well. Rena agrees that she must be as well. Chie enters apologizing to interrupt their Club activity to tell Rika that she has a visitor.

Ōisihi waits for her outside. In his air-conditioned car, he informs Rika that Tomitake Jirō and Takano Miyo died on the night of the Watanagashi Festival. In her Adult Voice, Rika narrates as she looks at the photograph of Jirō: "Yes. That's how it is. Fine. I'll play with it during this endless June." Over the view of the dead higurashi normally seen in the End Titles, she adds: "As much as I want.", right before it switches to the series logo, usually seen in the opening theme.