Early summer, Maebara Keiichi had just moved to a remote mountain village. As he becomes close friends with a group of girls, he was enjoying his life in the village. However, when he starts to become suspicious that Ryūgū Rena, Sonozaki Mion and the others that Keiichi trusted may be deeply involved in successive murders that occur every summer, the situation around Keiichi gradually starts to turn. As if the girls' characters had completely changed, a sewing needle is found in his food, he is chased by mysterious men, and is involved in an accident that could have killed him. He could no longer trust anyone, and then one mystery leads to another, bringing out a shockingly bloody ending.

과거에 마을에서 일어난 끔찍한 미해결 사건의 소문을 듣게 되면서 벌어지는 이야기

昔から伝わる「綿流し」という神事を行う村・雛見沢村を舞台に巻き起こる凄惨な連続怪死・連続失踪事件の謎を描いた連続式のミステリー作品。舞台は村人の連帯が強固で一見平和な村に見える雛見沢村。ここに少年・前原圭一が引っ越してくる。新たな学校や友人と楽しい学校生活を送っていた圭一だが過去に村で起きた陰惨な未解決事件の噂を耳にしたことから日常は綻び始める・・。