During Rika's ritual performance at the Watanagashi Festival, Shion whisks Keiichi away to sneak into the forbidden shrine warehouse, where Tomitake and his friend, Miyo Takano, are waiting. However, after learning about the other pair's fate, he starts to worry about his and Shion's safety.

Satoko is absent from school for a few days. After discovering that the cause of her absence is Teppei, her abusive uncle, who left Hinamizawa after his wife was murdered on the night of Watanagishi, but recently has returned, Keiichi decides to intervene.

Shion has captured the village head and gets information about the town involving the previous murders and Satoshi. Later, Shion confronts Rika about the murders, leading to a confrontation between the two. Once night falls, the truth behind Rika and Satoko's disappearance at that night is revealed.

While studying Takano's scrapbooks, Rena starts to unveil the the truth behind Oyashiro-sama and Hinamizawa's dark past.