Rage Against the Dying by Becky Masterman

Brigid Quinn, now retired and living in Tucson with her new husband, Carlos, regrets the way her career ended with the FBI.  When a man is apprehended by the police and he seems like he could be a suspect in the unsolved Route 66 murders, Brigid gets involved--albeit unofficially--because it was a case she worked on.  A young fellow FBI agent, Jessica Robertson, was actually the last victim of the killer years ago, and Brigid holds herself responsible for her disappearance. The suspect, Floyd Lynch, knows a lot about the Route 66 murders and has information that was never released to the public, but is he the real killer?  Brigid, trying to keep her violent past secret from her husband, finds herself caught between wanting to solve the case and exposing secrets which could cost her her marriage. Brigid reminds me of an edgier Kinsey Millhone and the story itself is more graphic than Grafton's mysteries.  But what a joy to find a new suspense novel to recommend.  It really is a complete package. The book will be published next month.