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.

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