Quiet and reliable, Douglas Ashburner has never been much of a womaniser. So when he begins an extra-marital affair with Nina, a bossy, temperamental artist with a penchant for risky sex, he finds adultery a terrible strain.

He tells his wife that he needs a rest, so she happily packs him off for a fishing holiday in the Highlands. Only, unknown to her, Douglas is actually flying off to Moscow with Nina, as a guest of the Soviet Artists' Union. It is then that things begin to get very complicated indeed...