Who And Why

By WILLIAM A. HENRY III

A CITY OF STRANGERS

by Robert Barnard

Scribner's; 287 pages; $18.95

BONES AND SILENCE

by Reginald Hill

Delacorte; 332 pages; $17.95

Classic British mysteries generally fit into one of three categories: the puzzle, or whodunit; the psychological study, or whydunit; and the comic jape. Robert Barnard and Reginald Hill have each written deft examples of all three. In their newest and most ambitious works, they adroitly fuse the subgenres together to paint rich, if characteristically jaundiced, social panoramas of decaying industrial towns. Both offer the teasing pleasures of suspense, sly misdirection and a breakneck climax as police seek to avert bloody murder. $ Both feature a gallery of vivid characters. And both take on themes ostensibly belonging to serious literature.

Barnard's concern is what makes people "nice," and he homes in on the distinctions between virtue and conformity. His central characters are the Phelans, a scruffy clan of hoodlums, vandals, welfare cheats and general layabouts who are burned out of their home in a fatal arson. Not even this makes them sympathetic. They remain a bitter if invigorating tonic, to be taken in carefully measured doses. But they are mean-spirited fun. Barnard, an acute and merciless chronicler of Britain's middle classes, is at his fiercest in showing how the proper bourgeoisie reacts to, and is repeatedly bested by, the convention-scorning Phelans. The story's most intense drama is generated not by the search for the killer, but by the question of whether the one decent-seeming Phelan, an amiable schoolboy, is for real and will stay that way.

Hill's interest is the various and ever changing ways to define success. At first the story seems to look outward, at how anyone's ambitions reveal his or her class and background. But the focus gradually shifts inward, to a deepening psychological exploration of a writer of anonymous suicide threats, and reveals how much a successful person may depend on the reaction of others to provide a missing sense of self-worth. At the center of Hill's plot is an outdoor-extravaganza staging of a medieval "mystery" play -- a cunning hint from Hill that his work, like its Middle Ages namesake, is more concerned with moral and metaphysical conundrums than with clues to some mundane crime. The final scenes, set aptly in a Gothic cathedral, convincingly merge a police procedural with a plunge into a soul in torment.