Kadota, a veteran tour escort working for the travel agency that organised a ‘25-day all-female tour of Europe’, sets off from Japan alongside Hijikata, who has been handpicked as the tour guide following a forceful recommendation from Egi, a travel journalist popular with wealthy ladies. Amidst a tangled web of rivalry and jealousy amongst the participants, and with the future of the tour looking uncertain, the group encounters a series of strange incidents—including a theft—at their refuelling stop in Anchorage and their first sightseeing destination, Copenhagen. Although they manage to avoid involving the police and the tour continues, events finally escalate in Scotland, culminating in the murder of one of the tour participants. Eventually, everyone involved is gathered in Switzerland, and tour guide Hijikata begins to unravel the mystery of the incident...