25-year LAPD veteran Harry Bosch comes back to the force after 3 years of retirement. This time, he and his partner, Kiz Rider, are working in "Open Unsolved," a top-notch homicide unit that applies new technology and cutting-edge investigative techniques to closed cases. Formed during Harry's retirement, the unit offers the victims of crime and their families one more shot at justice, but as the detectives working these cases know, time is not on their side. The evidence (such as it is) is old, and the leads are far from fresh. Harry's first assignment involves a cold hit on a DNA sample from an unsolved 1998 crime: the disappearance and subsequent murder of a lovely 16-year-old girl. From the first it's clear that the original detectives on the scene missed vital clues, and Bosch doesn't win any points by criticizing their mistakes. Fortunately, he has always cared more about justice than popularity; and as the fascinatingly complex investigation unfolds, he is determined to make things right--even if that means hanging his fellow cops out to dry.