CRIMINAL PURSUITS

Writers who follow a protagonist through a series of titles either go stale in the format or use it as a secure footing to tackle more adventurous material. Nancy Pickard has led her Jenny Cain through six previous books, each clever and warm, with a good sense of the small New England city where Cain runs a charitable foundation. (Last time, in “Bum Steer,” she detoured to the Midwest, where Pickard actually lives.)

None of the earlier works prepare you for the intensity of I.O.U. (Pocket Books: $17.95; 234 pp.), an unhappily titled but very affecting story of Cain’s search for the truth about her mother, who has just died after years in a mental hospital. No mystery about the death; the question is what stresses and horrors had caused the mother’s crackup so many years ago.

There is a mystery, to be sure, the collapse of the family’s cannery, which cost jobs and left deep wounds in the town. The converging trails to her mother’s sad past and to the villainous authors of the bankruptcy both are deftly handled.

But it is Cain’s anguish--doubting her own sanity (as many of the townspeople do); racked with guilt, deserved or not; foundation job sacrificed to her obsession--that pushes Pickard’s book toward the presumed limits of the crime form and in the end lift it beyond the usual tidy diversion.

The pseudonymous John Sandford, actually Pulitzer-Prize winning journalist John Camp of St. Paul, Minn., writes mysteries under both names. As Sandford, he has done two previous police procedurals, “Shadow Prey” and “Rules of Prey,” both featuring a homicide detective who is rich (from inventing computer games) and burnt-out. In Eyes of Prey (G. P. Putnam’s Sons: $19.95; 318 pp.) there is no doubt who the perps are (as we say in the police trade). They are a drug-drenched hospital pathologist who is a pathological killer at heart, and an uncommonly ugly juggler/actor whom the doctor recruits in a kind of “Strangers on a Train” murder-swap.

The murders are particularly ugly, involving mutilation, and the story’s genuine suspense is whether Davenport or anybody else can nail the killers. The author knows his procedures, his city and his characters very well. His descriptions of the doc’s three- and four-course drug meals take you inside a very sick man. You may not want to be there, but there is a terrible fascination about it. Sandford’s ear for dialogue is excellent, and the story’s action is relentlessly swift.

The 1,000-mile Anchorage-to-Nome dog-sled race called the Iditarod after the trail (“faraway place” in the Athabaskan Indian tongue) makes news every year, the marathon to end all marathons, which has been won by women as well as men in equal competition. It’s a literally far-out setting for a murder mystery. Then again, author Sue Henry lives and works in Alaska and knows the territory.

Murder on the Iditarod Trail (Atlantic Monthly Press: $19.95; 277 pp.) is more interesting for the race lore than for the mysterious murders, but the race lore is engrossing and the you-are-there credibility of the story would have you believe that Henry has mushed along herself. In truth, she gives early clues to the killer, who is snarlingly clever, but it hardly matters. The killings are refreshingly unusual (if that’s the term I’m seeking). A budding romance between an investigating detective and one of the women competitors is brusquely charming. And the howling winds, the snow, the ice, the dancing away from wolves, the crazing fatigue, the welcome heat and food, are almost palpable.

Jane Langton’s The Dante Game also is far afield, but in civilized and temperate Florence, which the author herself has captured in unshaded ink sketches that illuminate every chapter in a quite enchanting way. The setting is a new school for American students interested in Dante and his city.

The school is a kind of academic Fawlty Towers and becomes unwittingly part of a plot to assassinate the Pope on an early Easter Sunday morning visit to the city. One of the students, a beautiful young woman, becomes a hostage, sought by a nice young man who loves her and by a bumbling Harvard ex-professor named Homer Kelly, who has bumbled through seven previous mysteries and is a sideline figure here.

The real villain is, curiously, not brought low, which suggests that the author shares a rather sardonic view of life with, for example, Patricia Highsmith, although Langton is generally not so dark, and she has a fine way with offbeat characters.

Talk about series characters. William X. Kienzle’s Father Koesler of Detroit has had a dozen previous adventures, commencing with “The Rosary Murders.” In Chameleon (Andrews & McMeel: $16.95; 286 pp.), a prostitute dressed like a nun is bumped off, which causes a furor because her sister really is a nun and it may be a case of mistaken identity. The killing of church people continues, up to and including a retired archbishop.

For all the plotting, Kienzle’s book (like Nancy Pickard’s story of the search for the reality of a mother) seems a carrier for deeper thoughts. Kienzle, a priest for 20 years who left the priesthood, but not the Church, to marry, has Koesler and the other characters muse profoundly about such issues as clerical celibacy, the ordination of women, papal authority, the new liturgy and the other legacies of Pope John XXIII.

The divisive debates about these issues are at last not unrelated to the crimes at hand. The material may also be, to coin a phrase, too parochial for some readers, yet there is the pleasure of reading an author who knows the territory from inside and out and whose characters, up and down the hierarchy, are drawn with a pen that can be very, very sharp.

Robert K. Tanenbaum, a former assistant district attorney in Manhattan and former mayor of Beverly Hills, where he now lives, has written two previous novels. Immoral Certainty (E. P. Dutton: $18.95; 282 pp.) is a grisly item involving Satanic rites tailored to murderous pedophilic tastes, with practitioners at the highest levels of law and order.

A converging plot involves a psychopathic young killer and a childlike giant who cries “I want my mommy” in moments of stress, most of them caused by Mommy herself. Like the many other lawyer-authors, Tanenbaum knows the workings of the criminal courts, which to the reader may well be as frightening as the bloody Satanic rituals.

The intricate plotting builds to a rousing finale; a romance between two assistant D.A.’s is nicely observed, and there are candidates to add to an anthology of rotten judges. Yet the net effect is less than wholly satisfying because the realities of a sub-genre we can call the law procedural do not meld well with the Grand Guignol of the Satanists.