You've got to be very fond of police procedure for its own sake to stick with this Sedona County, Cal., investigation--which traces two slum street mutilation-murders (face shot away, hands cut off and disposed of) to a robbery ring and police corruption. The big problem, of course, is identifying the anonymous bodies; an imaginative Identi-kit artist goes to work on one corpse, the other is traceable because he recently donated blood, a rare type. And then the police must find a connection between the two victims, now identified as a malcontent cop from a nearby station and a freelance security guard. Only one other clue: a pen found at the scene of the crime that points to a certain storage company. Solid, believable, contemporary sleuthing, partly computerized and partly just legwork--but no character to tag along with and no suspense to speak of.