The Sweetness at the Bottom of the Pie - Alan Bradley

It is June 1950, and a sleepy English village is about to be awakened by the discovery of a dead body in Colonel de Luce's cucumber patch. The police are baffled, and when a dead snipe is deposited on the Colonel's doorstep with a rare stamp impaled on its beak, they are baffled even more. Only the Colonel's daughter, the precocious Flavia - when she's not plotting elaborate acts of revenge against her nasty older sisters in her basement chemistry laboratory, that is - has the ingenuity to follow the clues that reveal the victim's identity, and a conspiracy that reaches back into the de Luce family's murky past.

Flavia and her family are brilliant creations, adding a darkly playful and wonderfully atmospheric flavour to a plot of delightful ingenuity.