There's nothing like a female detective with attitude, especially one who's paid her dues. Retired FBI Agent Brigid Quinn has attitude in spades. At fifty-nine, she has seen her share of predators and the damage they do to innocent victims. The case that still haunts her is the unsolved Route 66 Killer, a serial murderer whose last victim was an agent Quinn trained herself, snatched while trolling the highways, her team in radio contact. So far the young agent's body has not been recovered.

Other than the righteous shooting death of a suspect that mars her permanent record, Quinn is content in her retirement in Tucson, Arizona, newly married to ex-priest and retired philosophy professor Carlo Di Forenza. Quinn spends her days enjoying her husband and foraging in local river washes for rock specimens to add to their garden. Unfortunately, she has deemed it necessary to separate her former life from her current married state, worried that Carlo will view her differently if he knows how much violence she has witnessed as an agent.

That conundrum is exacerbated when a local deputy sheriff and family friend knocks on her door with an informal invitation. FBI Agent Laura Coleman is requesting that Quinn accompany her while escorting a murderer to the site of his last two victims. The man claims to be the notorious Route 66 serial killer, and he says one of the bodies is that of the missing agent. Quinn is drawn back into the case, desperate to put an end to his annual reign of terror on Southwestern highways but anxious that her careful facade will crumble under Carlo's scrutiny.

To make matters worse, an attack by a murderous sexual predator in a wash near her home ends in violence. Brigid makes a snap decision, the consequences of which not only affect the direction of the Route 66 case but jeopardize her marriage. Suddenly her deft manipulation of career and home life is threatened by the weight of an investigation she cannot resist and a lapse of judgment that destroys her credibility, her professionalism at issue. Once on the scent of the man truly responsible for her agent's murder, Quinn no longer has the capacity to dissimulate between the two worlds, Carlo aware that she is not telling him what is troubling her. Her new marriage is put to the test, Brigid convinced Carlo will never accept the woman she really is, a woman all too familiar with the dark side of human nature.

"This is Brigid Quinn, a woman of a certain age, raging." This sentence pretty well describes a character who suffers no fools, fails to trust the one man most likely to have her back, and chooses a network of lies rather than admit the truth of her desert encounter. Between the need to dismantle one case to prove another, the complications from the attack in the wash and Carlo's awareness of her violent history, Quinn barely has time to confront the killer and save Agent Coleman, convinced her recently discovered happiness has been forfeit to fate. This is a take-no-prisoners protagonist with great instincts and too much cynicism for her own good, rude, smart-mouthed and likable, our guide on a hell of a ride with surprising twists, a character just flawed enough to be extremely attractive.