Detroit is a city with a rather elusive quality. Not quite in the same way as Los Angeles, which elicited from Gertrude Stein her most quotable crack: "When you get there, there is no there there." No, there, is a "there" to Detroit, all right -- tough, ramshackle, raw and ugly -- a phoenix with clipped wings struggling vainly to rise from its own ashes. But there is more to the city than that. It is a place of opposites -- ethnics, black and white, rich and poor -- attracting, repelling, clashing, whirling in constant flux. Perhaps Detroit's elusive quality is simply that of a city still becoming -- one not yet fully defined.

If, however, all this "perhaps" talk of phoenixes fails to enlighten you, then you can do no better than to read Elmore Leonard's "City Primeval." It is a candid, unretouched picture of life in the city today, as viewed mostly through the jaundiced eye of a homicide dectective. As such, it is a "genre" novel -- crime, police procedure, etc. -- but it is such a piece of artful simplicity that it manages to suggest the entire macrocosm of the city within the microcosm of its gritty plot.

His cops talk like cops, and they think like cops. But his lawyers also talk and think like lawyers. And Judge Alvin B. Guy of Recorder's Court (whose murder precipitates the nasty chain of events that leads to the duel between murderer and detective promised in the novel's subtitle, "High Noon in Detroit") could well have been drawn directly from life.

Judge Guy is corrupt, foul-mouthed and abuses his office with such arrogant aplomb that he might have been put away by any one of hundreds of people on either side of the law. As it happens, however, he is shot to death in a fit of cold rage by Clement Mansell, a psychopathic criminal up from Oklahoma, who doesn't even know the identity of the man he has killed. Lt. Raymond Curz of Squad Seven of the Detroit Police Homicide Section, who himself had so little use for the judge that he testified against him in a Judicial Tenure Commission proceeding, is in charge of the investigation of his murder.

It is a mark of "City Primeval's" authenticity that Squad Seven really does exist, and it is located exactly where Leonard says it is in police headquarters. He must have hung around for months to get the sounds, sights and feeling of the place just right. Not only that, he must also have gone out often with detectives on their rounds, for the details of police investigation -- the careful, almost monotonous, routine of fact-gathering -- are handled about as convincingly here as they ever have been in any crime novel. And what with television's "Kojak" and Ed McBain's 87th Precinct novels, we've all become quite sophisticated about these procedures.

But Raymond Cruz is no Theo Kojak. He is a well-drawn, rounded character; a believable human being. He is intelligent enough to be very good at what he does, yet has only the degree of sophistication (or lack of it) that a Detroit police lieutenant would be likely to have. And he is just one of a whole cast of well-realized characters. Carolyn Wilder, the lawyer on the other side of the fence, although not quite convincing, plays the role in which Leonard had cast her with style and spirit. Crazy Clement, a.k.a. "the Oklahoma wildman," and his spacy girlfriend, Sandy Stanton, are presented with chilling reality.

Admittedly, the lot of "City Primeval" is not without a certain melodrama.

Yet it all hangs together so well, and is worked out so logically, that when the final confrontation between Cruz and Clement comes, it seems almost to have been preordained by fate -- and not merely by the author.

This is Leonard's 19th novel. The first five were Westerns, more or less, and they included "Hombre," which Paul Newman and Martin Ritt made into a pretty good movie. (There are, of course, unmistakable and quite intentional echoes of the Old West in the cop ethos of "City Primeval.") Since then he has worked nearer home, using his hometown as the setting for his best books, which are all thrillers -- most of them so well and cleanly written that they press hard against the limits of the genre. He's doing for Detroit what George V. Higgins has done for Boston -- illuminating the city by exposing its underside, showing us Detroit for what it is, not for what it would like to be.