In Sicily, where people do things as they please, Inspector Salvo Montalbano is a bona fide folk hero. In THE TERRA-COTTA DOG (Viking, $21.95), Andrea Camilleri's populist detective shows his contempt for the ''extortionists and grafters, bribe takers, liars, thieves and perjurers'' who constitute the local power structure by maintaining a friendship with a drug-dealing pimp and performing a humanitarian service for a major Mafia figure. A man of lusty appetites who declares himself ''deeply moved'' by the dishes of fried mullet, boiled squid, poached baby octopus and other fishy delicacies on which he heartily dines, Montalbano tears into books and new ideas with the same gusto. When a reference to a scholarly thesis called ''The Use of Macaronic Latin in the Mystery Play of the Seven Sleepers'' helps him crack a gunrunning enterprise that goes back to the black market days of the Allied occupation, he runs out on the beach and turns cartwheels. Stephen Sartarelli's translation from the idiosyncratic Sicilian dialect savors the earthy idiom and pungent characterizations that Camilleri uses to cushion the impact of his story, which opens in opera buffa style with a botched supermarket heist, only to darken with comic gravity into a wartime horror story that lives on in a people's collective memory.
Marilyn Stasio