The body of neighborhood nuisance Tatsuya Amagi is found in the park of a high-class neighborhood. He was stabbed numerous times by an awl-like weapon. Next to the body is the bloodstained medical examination card of neighborhood association president Hikoichi Bando. The police head to Bando's home to question him, but discover Bando has been poisoned with a combination of liquor and pesticides, and near his body is a bloodstained awl.