Detective Chief Inspector Gil Mayo's fourth case (Requiem for a Dove, 1990, etc.) opens with a corpse in a Porsche whose face has been obliterated by a shotgun blast. The gun belonged to well-to-do septuagenarian John Culver, and the car to his son-in-law, Rupert Fleming, whom he hated. But the corpse, Mayo discovers, is really theater-director Ashleigh Cocayne, who, with Rupert, had a porno- picture sideline going. Now Rupert is on the lam, and no wonder: he killed a copper who'd come snooping; he killed his porn partner; and he stole from his father-in-law and then begged funds from his wife to provide for his other ``wife.'' Mayo's steadfast tracking of the elusive Rupert leads him through the village and environs to a set of neatly placed flagstones--and what's underneath them--for a dreary, all-too-telegraphed ending. So-so, but with ample cozy attributes--thanks mostly to that English village setting.