ANTONIA FRASER, historian and scholarly biographer of Mary, Queen of Scots, and Oliver Cromwell, brings the same lively and inquiring intelligence to the writing of her Jemima Shore mysteries. Both her fortes, history and mystery, come together in felicitous union in The Cavalier Case (Bantam, $17.95).

Jemima, a television investigative reporter in London, finds herself in love again -- this time with the person in a portrait of a Cavalier poet-soldier who has been dead for more than 300 years. The object of her new passion is Decimus Meredith, First Viscount of Lackland, mortally wounded in 1645, whose body mysteriously disappeared before burial. About the same time that Jemima receives the portrait from a friend for safekeeping, the 17th viscount dies in a fall, not too surprising for a half-drunk, half-blind man of 77.

Fascinated by the poet-soldier's portrait, Jemima is quick to suggest that she go to Lackland Court to do research for the opening segment of a projected television series on romantic ghosts haunting the stately homes of England. There she is to meet "Handsome" Dan Meredith, the new viscount, who can be every bit as attractive as his Cavalier forebear.

"Handsome" Dan, tennis champion and ladies' man, would like to recoup the family fortunes by converting Lackland Court into an exclusive tennis club. He has an expensive lifestyle and a raft of responsibilities, including Nell, his strange, fey daughter by his first marriage and a brood of three blond youngsters, one of whom is the male heir, by his second wife. Then there is Dan's red-haired mistress. As a matter of fact, his elderly cousin's death in a fall, leaving title and Lackland Court to "Handsome" Dan, could not have come at a more propitious time.

Jemima's feature story on ghosts soon becomes a tabloid front-page story with murder, sex, sport, scandal and the supernatural. An old butler falls to his death from the battlements of Lackland Court, the ghost appears, and the murderer is unveiled during a sound-and-light enactment.

All this is told by Fraser with wickedly droll wit as she skewers the pretensions of snobs and television executives with equal relish. She can parody Cavalier love poetry with the line: "I fain would be thy swan . . ." May Jemima have more adventures and love affairs with both present and past. Death in the Desert WITH ONLY her third appearance, Neil Hamel, the Albuquerque lawyer-cum-sleuth, quickly establishes herself as a series heroine with her own distinctive style and voice to stand out in the swelling crowd of female sleuths. Sue Grafton's Kinsey Millhone and Sara Paretsky's V.I. Warshawski are their own women. And so is Neil Hamel, as she again forcefully demonstrates in The Other Side of Death (HarperCollins, $18.95)

Judith Van Gieson gives us a tough-minded, sensual woman with self-mocking honesty in Neil, who, as she herself puts it as the narrator, "belonged to a generation of dead heroes and prolonged adolescence." She and her friends had carried the spirit of the '60s into the early '70s in a small Mexican village as they drank together, took drugs together and slept together. When life intervened, Neil went to law school and set up private practice in Albuquerque while the others gravitated north to Santa Fe.

Now, nearly two decades later, the old crowd is getting together to bid goodbye to a couple moving to heartland Ohio. As happens in another such reunion in the film "The Big Chill," there is a death that raises questions about past and present relationships.

Lonnie, still a child of the '60s, is found dead, a lethal mix of drugs and alcohol in her blood, in the ruins of an Indian cave where she sometimes went to meditate. The police dismiss her death as the suicide of a depressed substance abuser.

But Neil, who had driven the drunk Lonnie from the party and stayed at her friend's Santa Fe house to wait out a snowstorm, is not convinced that Lonnie's death is a suicide. There are too many unanswered questions. Why would Lonnie go off in the middle of the night and a snowstorm to meditate in the cave? Where is the sleeping bag missing from her car? Where is the journal Neil saw in the bedroom? And there was something in Lonnie's talk about bribes paving the way for the "Ugly Building," a downtown project being picketed by protesters.

Neil's investigation takes her to a developer's chic party and a tattoo parlor before her own life is threatened in a harrowing attack by a murderer.

Neil applies her acerbic wit to herself as well as others. She is not afraid to make choices in her life. And that includes the Kid, a younger mechanic-accordionist, who is her lover. Their relationship is tenderly passionate without many words spoken.

Van Gieson's Southwest landscape is spectacularly beautiful. In the lyrical opening passages, she makes you feel spring as it moves northward at a walker's pace from the El Paso border.Music and Murder WHEN THE music teacher is garroted with a G-sharp piano wire, the medical examiner, who must relax to classical music after a day at the autopsy table, muses: "Chopin wrote the impossible Double Thirds Etude in G-sharp, and everyone thought that was a killer."

The boorish police lieutenant, who has risen in rank far above his abilities, isn't interested in concert notes. He thinks the medical examiner's other information -- the murderer probably was 6-foot-3 and ambidextrous -- will provide telling evidence for the arrest of his number one suspect.

Could there be a more unlikely murder suspect than Leo Perkins, a middle-aged chess player and furniture saleman? Leo is living on the edge of his income to pay the mortgage and give his daughter piano lessons with slick, swaggering Harmon Parrish, who has become a status symbol among Leo's wealthier neighbors in suburban Westchester County. Parrish well may be offering more than piano lessons when he visits the homes of his pupils.

In Furnished for Murder (St Martin's, $15.95), Richard Barth offers another senior-citizen sleuth as a counterpart to feisty Margaret Binton, who has appeared in a half-dozen of his earlier mysteries (The Ragged Plot, The Condo Kill, Deadly Climate). This time it's Jakob Barzeny, the champion at Leo's chess club and a Russian Jewish emigre who was a Soviet policeman before fleeing Khrushchev. Jakob views the murderer as a chess adversary whose moves must be anticipated for a checkmate.

Barth never is condescending to his senior citizens. They are survivors, shrewd and streetwise in their own way, who have had time to achieve a perspective on life. In Furnished for Murder, Barth proves murder can be as deadly in the quiet suburbs as in the violent streets of big-city Manhattan. He also offers a surprise killer and an ingenious murder method. I have a nagging doubt about one or two details, but let's not quibble and enjoy the delightful company of Jakob and Leo.On Location THERE IS AS much tempestuous drama behind the scenes as on the location set as a movie crew prepares to film a novel of 19th-century sex and violence against the background of a rocky coast of Western Scotland. In Jill McGown's Murder Movie (St. Martin's, $17.95), life -- and death -- soon imitate art.

Frank Derwent, a director with a casting-couch taste for blue-eyed, blonde bimbos, is tyrannical, malicious and deservedly hated by all. He has assembled a cast and a crew that include Barbara Slaney, his latest mistress; Wanda, his alienated wife who is writing a tell-all Hollywood book; an aging soap opera star; a handsome all-American leading man; a veteran actor who once was married to Wanda; a novelist who sees his book being butchered on film; and an assistant director who has become protectively cynical working under Derwent.

When Barbara and Wanda die in quick succession, Derwent is the suspect with the obvious motive in both cases. But his alibi seems to eliminate the opportunity for him to have committed the murders. Another victim must die before Detective Patterson, who himself has an emotional tie to one of the cast, puts together motive, means and opportunity to trap the killer.

In her latest mystery, McGown pursues cleverness at the expense of clarity and narrative pace. In the end, it doesn't seem worth the effort to sort out all the illusions and complicated time sequences to understand how a murderer nearly escaped. This is really rather unfortunate for McGown has proved herself a stylish, inventive writer with her earlier Murder at the Old Vicarage and Gone to Her Death. Jean M. White regularly reviews mysteries for Book World.