Masaharu Fukuyama returns to his role from the 2008 film “Suspect X,” portraying the physicist-turned-detective Manabu Yukawa. The scientist-detective travels to a coastal town to participate in a panel discussion. However, when a man is found dead outside the inn where Yukawa is staying, he starts to piece together the links between the deceased, the innkeepers’ activist daughter, and a clever young boy who initially appears on a train and continues to reappear. This mystery, reminiscent of Sherlock Holmes, incorporates an environmental angle and is sure to delight fans of traditional whodunnits.