Fukami, a secretary engaged to company president Kaido, her employer, is invited by his close friends, the Nogis, to a three-day-two-night tour. The tour group is traveling in a luxurious coach to Lake Megami in the Tateshina Plains. On the way, they are disturbed to hear that Shirai, a hostess who was supposed to come along on the tour, has been murdered. And the next day, the body of Hasegawa, another tour member, is floating in Lake Megami...

Ce synopsis est en anglais : nous ne l'avons pas encore traduit.