One Christmas, a foreign detective stays with an English family in their ancient manor house in the countryside. His hosts at Kings Lacey believe he is there to experience an old-fashioned English Christmas. In reality, he has been hired by a senior state official to prevent an international scandal and recover a stolen ruby. The detective enjoys Christmas with all its traditions and trappings — a decorated tree, filled stockings, stuffed turkeys — but is initially wary of the Christmas pudding. This large ball of a dessert looks impressive, “a piece of holly stuck in it like a triumphant flag and glorious flames of blue and red rising round it.” But the previous night, he found an anonymous note in his room containing a short, stark warning: “DON’T EAT NONE OF THE PLUM PUDDING. ONE AS WISHES YOU WELL.”

This cryptic note heralds more disturbances that cast a shadow over the festivities. Someone drugs the detective’s coffee, then searches his room. On the morning of Dec. 26, some children attempt to “make him feel at home” by staging a mock murder. But the prank backfires when the person pretending to be dead in the snow turns out to have no pulse. Shortly afterward, the body disappears. “Someone,” the detective remarks, “has turned the comedy into a tragedy.”