TOUCH-ME-NOT. By Cynthia Riggs. Minotaur Books, $24.99.

It boils down to this: The mystery series that we long to pick up as soon as the new installment is released provides us with a world in which we love to wander, for which we gladly leave our own milieu. It’s probably beyond an author’s control, how this delight in atmosphere is achieved. In the case of West Tisbury writer Cynthia Riggs, and her successful series featuring 92-year-old poet, gardener and deputy detective Victoria Trumbull, also of West Tisbury, this idyllic placement of reader-in-setting grows from book to book.

The proof comes at the moment that the novel ends and the reader must return to real life. The urge to have available one last chapter arises. Instead of doing one’s own dishes, the reader contemplates an extra denouement with Victoria over her own kitchen sink, perhaps joining her vicariously for one of her simple, tasty meals which includes a salad from her garden and some salty conversation before the lights go out on the lane near Mill Pond.

As she has done in her eight preceding Victoria Trumbull mysteries, Ms. Riggs employs a clever device of deploying a sinister flower in the title (e.g. Deadly Nightshade, The Cranefly Orchid Murders, and The Cemetery Yew). This one is Touch-Me-Not (Minotaur Books, $24.99), named for a plant which grows uncannily within thickets of poison ivy and, when rubbed on the skin, serves as an antidote to its neighbor’s depredations.

The metaphor works beautifully for all the plot-lines in play: A stalker is at large, and is this the same perpetrator who has hidden cameras in young women’s showers? And what about the body that turns up in the bookshed behind the library? And why is someone targeting the ladies in the knitting group with bated breath phone calls?

Ms. Riggs paints an intriguing portrait of a family man, an able electrician, well-respected in the community, who is slowly unraveling from a series of events seemingly beyond his control. His failing marriage, an act of violence, spiraling guilt, all is kept hidden – protractedly so — in the compressed atmosphere of year-round Martha’s Vineyard.

At the same time, Victoria is beset by her own personal problems. As happens so often in families, understanding has skipped a generation.

While Victoria and her granddaughter Elizabeth live compatibly under the same roof, the woman in the middle — Victoria’s daughter and Elizabeth’s mom, Amelia, who comes to visit — is hopelessly out-of-tune with both of them, micromanaging her mother as if she’s a frail old lady rather than the super-sleuth, bionic grandmother that we’ve come to know and love in the series. It’s no secret to fans of Ms. Riggs’s that Victoria is based on the author’s late mother, the poet Dionis Coffin Riggs, 1898-1997. For those who can do the math, yes, Dionis died at the age of 99, still very much in her prime.

Ms. Riggs has perfected the art of the mystery form known as the cozy, a never too-too-violent tale, traditionally set in a picturesque locale where, in actual life, homicides come along once every century, century-and-a-half. Characters are colorful, and Ms. Riggs rolls them out like multiple dice in a felt-lined cup: there is Casey, the chief of police who has learned to let her deputy, Victoria, do all the major noodling; there is Myrna Luce, the sassy attorney with beaded, dreadlocked hair; and Bill O’Malley, college grad and gallant driver of a cobalt blue dump truck, always ready to run the aged detective on her errands in his lumbering chariot.

And, watch out, or the West Tisbury writer will put you smack in the middle of her fiction, as she has done in Touch-Me-Not with Diana and Whit Manter, Unitarian minister Rev. Judy, Lucinda Chandler and Jim Weiss. Before you think libel suit, each year Vineyarders vie at charity auctions to have their names inserted and their characters impugned (kidding!) in the next Cynthia Riggs mystery. The bad guys are all figments of Ms. Riggs’s imagination.

Another aspect of the cozy which Ms. Riggs observes is the kindly satire poked at earnest small town personalities. In Touch-Me-Not this mocking motif is accomplished with the mathematical knitting group keen on winning a national quilting prize with projectiles of fabric designed to depict the effect of global warming on oceans and coral reefs. And of course, this is a mystery, so we remind ourselves that nothing is what it seems. Knitting needles also could serve as deadly weapons, considering that one jab in the carotid artery could do a great deal of damage. Thus even in the midst of this giddy and goofy group, conceivably a murderer harbors his or her weapon of choice.

It’s all great fun, with Vineyard settings, both scenic and psychological, at every turn. And in addition to the cozy, Ms. Riggs has perfected the country law enforcement procedural, so perhaps she, like her sharp, engaging protagonist, also spends quality time at the desk of the West Tisbury chief of police.