Local citizens beware: a cold-blooded murderer is prowling the perimeter of Flathead Lake, terrorizing the area from Whitefish down to Bigfork and Polson.

At least, that’s the premise of “Sapphire Trails,” a brand new “whodunit” mystery novel by award-winning author Marilyn Jax.

The book is the third installment in a series of mysteries based on the fictional exploits of private investigators Claire Caswell and Gaston “Guy” Lombard. Though based out of Miami, the super sleuths’ past adventures have taken them to exotic locales such as the Caribbean and the Greek island of Crete. This is their first foray into the Wild West.

The tale is centered around a brutal murder at a lodge on Woods Bay in Bigfork, though the storyline meanders throughout the area, with key parts taking place in Whitefish and Polson as well.

Jax, formerly a senior government enforcement investigator in her home state of Minnesota, says that her own personal connection to Montana helped to inspire the story’s setting. Her family has ties in the Bitterroot that date to 1906, and she has been a perennial visitor to the Flathead region for the past 12 years.

“I like to write about places I visit,” says Jax.

“The cities, the countries, wherever I write about, I like to be there and observe the people and the customs and the food and smell the air and really get a feel for what I’m going to write about. I feel that’s really important and I think it lends credibility and authenticity to my writing.”

Jax didn’t study up on cultural elements of the Flathead, alone. In the novel, the protagonists work closely with local law enforcement to solve the case, and Jax did her homework to ensure that her portrayal of the investigation was accurate.

“I conferred with the Lake County Sheriff… (about) different procedural things, to make sure that I was accurately portraying the procedure that would take place in a murder case,” Jax said.

Though not used by their real names, “the Lake County Sheriff and his patrol deputies are actively involved in the book,” Jax says.

“They were very, very helpful,” Jax says of her assistance from local law enforcement, adding that Lake County Sheriff Jay Doyle even made a point to attend the Bigfork Festival of the Arts- where her book was launched- and bought a copy of the story.

In addition to the Lake County Sheriff, Jax also consulted the Flathead County Sheriff, Whitefish Police Department, and the Montana State Crime Lab for help with procedural details.

Much of the plot focuses on Whitefish, which is victimized by a series of burglaries that authorities suspect are linked to the Bigfork murder. At other segments of the book, Polson is at center stage.

“A chunk of the story takes place in Polson,” Jax said. While waiting for results from lab tests to come back, “the two main characters go down to the Sandpiper Art Festival,” says Jax, who is a regular attendee of the festival in real life. While they’re there, a pivotal clue is revealed.

Readers may recognize one of the characters with whom Caswell and Lombard interact at the art show. That figure would be Polson’s own Charlie Fudge, who makes a cameo appearance and is the book’s only character that did not have his identity altered amidst the pages of the book.

Fudge, who sells handcrafted wooden bowls, says that his relationship with Jax dates back years, to when he first swapped her a bowl for one of the prequels to “Sapphire Trails.”

Bumping into Jax year after year at local art shows, upon discovering that her latest work would take place in Montana, Fudge naturally asked, “am I in it?”

“You are now,” Jax replied.

Besides Fudge, local readers will be able recognize the frame store on Polson’s Main Street, which is also weaved into the story. The fictitiously altered store owner and her young son assist in uncovering a crucial clue.

Fresh off its Bigfork debut, Jax’s brand new publication has yet to hit shelves in her native Minnesota, with its release slated for October. Two years in the making, the book appears to have been worth the wait, as it has been well-received by critics. Previous mysteries in the Caswell and Lombard series have garnered a number of awards, including the 2011 Benjamin Franklin Best Mystery Suspense Award.

The book also earns an endorsement from its guest star, Fudge. Currently about a third of the way through the book, so far, so good, Fudge reports.

“She’s an intriguing writer,” Fudge says of Jax, mentioning that he’s been a fan of her previous works.

For those wanting to pick up a copy of “Sapphire Trails”, it is available at select locations in Whitefish, Kalispell and Bigfork, and is also available online. More information can be found on the author’s website, www.marilynjax.com.