バラバラ死体が発見されたのは、信州の小京都、飯田市郊外の松川ダム。叔父甥間の借金がらみの単純な殺人事件と見た捜査本部は「犯人」の自殺が確認された時点で解散した。だが、この事件の背後に不自然なものを直感した飯田署竹村巡査部長は執拗に事件に喰らいついていく。大型本格社会派のデビュー作。

When the body of one of Nagano Prefecture's most prominent businessmen is found propped against a tree on Poison Plain, home of the legendary Demoness Maple, Inspector Takemura finds himself searching for the killer with the help and hindrance of an esteemed Tokyo professor and a beautiful university student. As the bodies begin to multiply in the sleepy mountain town of Togakushi, the three learn that the resemblance of the murders to those of regional folklore is more than a coincidence. This novel based on Japanese legend and written by famed author Yasuo Uchida will mesmerize mystery buffs as well as those interested in the culture and folklore of Japan.