Although it is autumn in the small English town of Bishop's Lacey, the chapel is decked with exotic flowers. Yes, Flavia de Luce's sister Ophelia is at last getting hitched, like a mule to a wagon. Flavia is not your normal twelve-year-old girl. An expert in the chemical nature of poisons, she has solved many mysteries, which has sharpened her considerable detection skills to the point where she had little choice but to turn professional.