The annual Watanagashi Festival finally starts, and everyone has fun feasting and playing games. However, in the following day, Keiichi is interrogated by chief police officer, Oishi, about a crime that occurred at the night of the festival, and he starts fearing the villagers might be involved in this and other similar incidents, like Oishi suspects.

Keiichi and Rena suspect that Mion might be related to Rika and Satoko's disappearance, and confront her at her house. There, he learns from her about the burden she carries as the heir of the Sonozaki family, and tries to dissuade her to surrender herself without success.

Keiichi's mentality is shaken when his friends tells him that he was actually at the Watanagashi Festival with them and Satoko still bemoans her uncle's abuse, despite being sure about having him dead. His confusion grows when he tries to unsuccessfully find the truth.

Upon talking with Ōishi, Shion finds out Satoshi has gone missing and decides to investigate further into the mysterious murders over the past four years. One day at the library, Shion meets Takano, who tells her more on the history of Hinamizawa and its dark past. As the story skips one year to the present day, similarities between Keiichi and Satoshi brings back memories of Satoshi to Shion.