One evening, the couple gets lost among the canals and is befriended by a forceful native named Robert, who takes them to a bar. Later, he insists on bringing them to his house where they meet his wife Caroline. Although the guests are at first shown great hospitality, it becomes clear that the hosts have a peculiar relationship with each other – Robert is the product of a sadistic upbringing and Caroline, who is disabled, has an uncomfortable masochistic view of men as being masters to whom women should yield.