In 1993, Harry Bosch was assigned the case of a missing person, Marie Gesto. The young woman was never found - dead or alive - and the case has haunted Bosch ever since.

Thirteen years later Bosch is in the Open-Unsolved Unit, where he still keeps the Gesto file on his desk, when he gets a call from the DA's office. A man accused of two heinous killings is willing to come clean in regard to several other murders in a deal to avoid the death penalty. One of those murders, he says, is the killing of Marie Gesto. In confirming the confession Bosch must get close to the man he has sought - and hated - for thirteen years.

Bosch's whole being as a cop begins to crack when he comes to realise that he and his partner missed a clue back in 1993 which could have led them to Waits and would have stopped the nine murders that followed the killing of Marie Gesto...