In this addition to the Harry Bosch series the detective has left the LAPD in difficult circumstances. He's now a private investigator and also works for the tiny San Fernando Police Department as a reservist (unpaid volutneer).
As the book opens Harry is hired by octogenarian billionaire Whitney Vance, who's frail and ill. Vance never married but thinks he may have fathered a child during a youthful affair with a Mexican girl. Vance wants Harry to search for this offspring, who would be heir to the mogul's fortune. Vance warns Harry that the investigation has to be hush hush because the directors of Vance's company - who are looking forward to taking power themselves - would resent a legatee (to put it mildly).....and the heir's life might be in danger.
Harry uses his considerable resources and contacts, and soon makes progress with the case. Harry is sure Vance's people are monitoring him, so he's careful to take evasive measures.....but are they enough? At one point a holographic will shows up and Harry brings in his half-brother, attorney Mickey Haller, to provide legal assistance. The half-siblings pull off some sneaky moves, and it's fun to see them working together again.
Meanwhile, Harry is also working on a case for the San Fernando PD. Harry and his partner, Detective Bella Lourdes, are trying to nab the 'Screen Cutter' - a serial rapist who wears masks, doesn't use condoms, and targets Latina women. Harry has connected previous unsolved rapes with more recent Screen Cutter assaults, and discovers there's a pattern to the timing of the crimes. Harry, always careful, keeps his Screen Cutter files in a locked drawer. When his papers are rearranged Harry is sure someone - maybe even the Captain of the SFPD - is secretly monitoring his investigation. But why?
While Harry works on the two inquiries a murder occurs in one case and a kidnapping in the other - which leads to a frantic police search. In between all the detective work Harry visits his daughter at college, takes her out to eat, and so on.....which provides a nice domestic touch to the story.
I enjoyed the book, though a couple of revelations at the climax seem rather unlikely. Still this is an engaging, well-written mystery, recommened to fans of the genre.