Eleven year old Arthur Henderson (or 'Farty' as he is always called by his sister, much to his disgust) has been brutally dragged away one Christmas to an old country house in Scotland for a family holiday. With no TV, and banned from electronic games, he and his new friend Henry must make their own entertainment while avoiding his irritating cousin's ridiculous (but very fierce) pink poodle, Petunia. The stack of Agatha Christie novels in the library helps. Late on Christmas Eve, three feet of snow falls. The ensuing blissful Christmas morning is turned upside-down when the sinister housekeeper with the roaming mole discovers that the expensive old painting, 'Madonna with the Three Boobies', is missing. Can Arthur and Henry solve the case before the snow melts and the culprit escapes?