The Decagonal Room Murder Case

A secluded island where, half a year ago, a mysterious mass murder took place. A small strip of land with flamboyant buildings—creations of the strange owner of this place, Seiji Nakamura, among others killed in that brutal slaughter. They say his ghost still wanders there in the dark… Is there any better place for members of a student detective club who love mysteries like these? The mystery they’re about to face isn’t one of the usual desk-bound puzzles they’re accustomed to. Unbeknownst to them, the amateur detectives took something precious from the deceased Nakamura—and now someone is craving revenge.

In accordance with the honkaku genre canon, from the very beginning we already know that these characters are fated to die. And as the story unfolds, we learn everything that will help us compete on equal terms with the desperate search for the murderer—alongside his future victims. And with an incredible detective whose name is Kiyoshi Shimada…