An old schoolfriend asks Miss Marple to visit Carrie Louise Serrocold, sensing that something is wrong in the gentle woman's household. Carrie Louise lives at Stonygates, a sprawling Victorian mansion that her idealistic third husband, Lewis Serrocold, has turned into a college and rehabilitation home for young delinquents. Surrounded by devoted family, earnest reformers, and the troubled boys who fill the estate, Carrie Louise seems serene and cherished, yet Miss Marple soon senses an undercurrent of tension running beneath the orderly surface. Stepchildren, in-laws, and dependants circle one another with old resentments and quiet ambitions, and the arrival of an unexpected visitor sharpens the unease. When a confrontation erupts and gunfire breaks out one evening, a death follows that no one can fully explain, and the household becomes a closed circle of suspects. Drawing on her instinct for human nature and her quiet attention to small inconsistencies, Miss Marple works alongside the investigating police to untangle what really happened. The mystery turns on the gap between what people are shown and what is actually taking place, as the apparent facts of the crime resist a simple reading. Set within a single charged household, the story examines reform, charity, and the way affection can blind even the shrewdest observer, while testing whether kindness can be told apart from manipulation. Miss Marple must look past the obvious staging to find the truth hidden in plain sight.