Looking back, 1975 was one of those years that sat on the cusp of change. Sure, the civil rights and women’s movements and the Stonewall Riots already had happened. But the pre-computer, pre-cellular phone year of 1975 was when things finally began to happen. P.J. Parrish richly taps into that time of change and its impact in the multilayered “A Thousand Bones” (Pocket Star Books, $7.99), which doubles as an exciting police procedural as well as a study about a young woman coming to terms with her ambition, her sense of self and her skills.

Of course, anyone who went through 1975 probably only felt a few ripples of change. That’s how it seems to Joe – Joette – Frye, the first female deputy in a sheriff’s department in a small, quiet town in upper Michigan. Her status as a rookie – but mostly because she’s a woman – make it easy for the other deputies to discount her and ignore her opinions.

The 22-year-old gets her chance to prove her mettle when human bones, indicating several victims, and American Indian symbols are found in the woods. None of the deputies, especially Joe, have ever handled such a big case, and its ramifications will affect each of them.

A spinoff of Parrish’s Edgar-nominated series about biracial detective Louis Kincaid (Joe is his girlfriend), the author skillfully makes “A Thousand Bones” the young woman’s own story, from her on-the-job education to a crumbling relationship with her college boyfriend.

Told in flashbacks to Louis, “A Thousand Bones” intensifies with suspense, insightful character studies and crisp dialogue. Parrish also peppers “A Thousand Bones” with many insightful details that Joe experiences as the department’s first female deputy, such as even the smallest men’s uniforms don’t fit. Scenes of a mother’s grief are simply heartbreaking. The tension accelerates as the plot deepens during the final chapters that are as stunning as they are controversial.

But “A Thousand Bones” stumbles early by showing glimpses of the villain too quickly, which is a frequent technique of the author. Still, this does not dilute the plot, and when the villain’s true identity is revealed it still has an impact.

Parrish, the pseudonym for sisters Kristy Montee of Fort Lauderdale and Kelly Nichols of Mississippi, delivers an exciting story with “A Thousand Bones.” Stories about Louis Kincaid are welcome, but we definitely want more Joe.