シリーズ前作『禁断の魔術 ガリレオ8』に続く書き下ろし作品。「週刊文春」2018年12月13日号では、この作品の最大の読みどころを「被害者の女性を大切に想っていたはずの人々がどのように犯罪に関わっていくのか」という展開だと指摘した。東野はインタビューで「被害者を愛した善良の人々が力を合わせたら、湯川でさえも手こずるような謎が生まれるのではと考えた」と語っている。
物理学家汤川学(福山雅治饰)从美国回到日本，女警内海薰(柴崎幸饰)向他寻求帮助。镇上一个很受欢迎的女孩突然失踪，几年后她的尸体被发现，汤川的同学、高级警探草薙顺平(北村一辉饰)逮捕了一名男性嫌疑人，但该名嫌疑人因警方缺乏证据而被释放。当这个男人回小镇里时，他又出现在了女孩家人面前，向他们挑衅。仇恨的气氛笼罩着整个小镇。 然而，就在秋季节日巡游当天，这个人死了，镇上每个人都有杀人动机，但也有不在场证明。汤川、内海和草薙着手破解这道难题。
Physicist Manabu Yukawa returns to Japan from America. Detective Kaoru Utsumi visits him and talks about a case. The case is about a popular girl in a town who disappeared and, several years later, her body was found. A suspect was arrested for her murder. That suspect was previously arrested for another girl's murder, but he was released due to a lack of evidence. Detective Shunpei Kusanagi investigated the prior murder case. The same suspect was then released due to a lack of evidence for the most recent murder case. The released man returned to his town, where everybody hated him. On the day of the autumn festival parade, the man was killed. Physicist Manabu Yukawa, Detective Kaoru Utsumi and Detective Shunpei Kusanagi work together on his case.
