CRIMINAL PURSUITS : SUNSET EXPRESS,<i> By Robert Crais (Hyperion: $21.95; 278 pp.)</i> : THROWN-AWAY CHILD,<i> By Thomas Adcock (Pocket Books: $21; 266 pp.)</i> : MASQUERADE,<i> By Gayle Lynds (Doubleday: $23.95; 384 pp.)</i> : FIRESTORM,<i> By Nevada Barr (Putnam: $21.95; 307 pp.)</i>

If it accomplished nothing else, the O.J. Simpson ordeal has served as a source of endless inspiration for comedians and writers. Robert Crais, whose novels about private detective Elvis Cole contain enough humor to place him in both categories, cleverly makes good use of elements of the “trial of the century” in his latest highly entertaining mystery, Sunset Express. Leaving the race card untouched, he presents a murder suspect similar to Simpson several ways--he’s wealthy, he’s accused of slaying his wife and he’s hired the best legal minds money can buy. His chief lawyer, enough of a grandstander to have a documentary filmmaker as part of his entourage, hires the private eye to investigate the female police officer who discovered the murder weapon at his client’s home. Did she plant it? True to Philip Marlowe’s tenets, Cole is more interested in morality than in money, and when he discovers that he may not be on the side of the angels, takes appropriate action. How he and his sociopathic partner, Joe Pike, seek to right the scales of justice makes for what may be the series’ strongest entry. The Crais fan club has been growing with each novel, and this one, his seventh, has the potential to make it all the way to the bestseller lists.

Thomas Adcock sends his series sleuth, New York police detective Neil Hockaday, to Louisiana in Thrown-Away Child. In just the first few pages of this, his seventh novel, Adcock switches point of view (from third to first person and back), changes tenses, lays out a flashback sequence and, in short, breaks about every rule ever proclaimed in a creative writing class. But it worked for James Joyce. And to a slightly lesser degree, it works for Adcock, as he Amtraks the ultra-Irish knockabout cop and his African American actress wife to New Orleans to visit her family. It’s no holiday for Hockaday. Not with an evil voodoo priest and an entrenched politician teaming up to knock down his in-laws. Once one grows accustomed to his stylistic razzle-dazzle, Adcock’s complex tale becomes a compelling one, enhanced by the attention it pays to children abandoned at birth. And his description of the Crescent City and its unique denizens rings true enough to make any native son, including this one, homesick.

Gayle Lynds’ Masquerade is an edgy, tricky thriller very much in the mode of Robert Ludlum’s coherent early bestsellers. Its protagonist is a beautiful, amazingly capable amnesiac. She is told that she is a government agent recovering from a bout with a super assassin known as the Carnivore. But she begins to distrust her abusive CIA contact and, before long, she and another member of the spy brotherhood, this one eccentric and charming, are on the run. Their plan is to avoid every law enforcement agency in the free world long enough to piece together her identity and, not incidentally, to undermine the nefarious earth-shaking scheme that has placed them in jeopardy. The result is a gloriously paranoid, immensely satisfying international thriller.

Although the long-standing advice about writing what you know is being questioned by those who value pure imagination over experience, the novels of Nevada Barr offer strong evidence in favor of the latter. Barr is a park ranger and, not coincidentally, so is her continuing creation, Anna Pigeon. In Firestorm, the fourth Pigeon mystery, the author describes a terrifying blaze sweeping across a section of Northern California with such authenticity and in such chilling detail that you can smell the smoke and taste the ashes. Equally convincing is her engaging heroine who, after barely surviving the conflagration in a little silver-cloth tent (affectionately called a “shake and bake”), must then, as security officer, figure out which one of the survivors murdered a monumentally disliked firefighter while the flames danced by. Snowbound, starving and days from rescue, she doggedly stalks the killer, a woman who obviously can stand the heat (as well as the cold). Barr is a splendid storyteller, but it’s her knowledge of the territory that ignites this fast-paced and suspenseful whodunit.