Mickey Haller, who has become increasingly frustrated in his role as a defense lawyer, agrees to undertake the prosecution role on behalf of the city of Los Angeles, in the retrial of a convicted killer which has been granted as a result of new DNA evidence. His one condition before accepting the task is that he is permitted to choose his own team; he chooses his ex-wife Maggie McPherson as his co-prosecutor, and his half-brother Harry Bosch as his investigator from the LAPD. The prosecution case rests largely on the testimony of Sarah Gleason, the elder sister of the victim, Melissa Landy.
The body of 12-year-old Melissa was discovered in 1986, discarded in a dumpster, only a few hours after she was reported missing. Unknown to the killer, her sister had been hiding in the garden and had witnessed her abduction. On the day of the murder, she identified Jason Jessup, a lorry driver, as the man who snatched Melissa from the garden. DNA evidence has subsequently shown that semen stains on the dress Melissa was wearing came not from Jessup, but from the girls' stepfather Ken Landy. However, the evidence against Jessup includes strands of Melissa's hair, found in the seat of his lorry.
Jessup's defense counsel, "clever" Clive Royce, mounts a media campaign in his client's favour, and it becomes clear that their main motivation is in obtaining a compensation payout from the state. Haller's response is to allow bail and have Jessup tailed by the police in the hope that he will return to his old ways and provide additional support for the prosecution case. Jessup is soon seen visiting various mountain trails in the Mulholland area, and on one occasion parks his car outside Bosch's house at night. Bosch and Haller, both concerned for their own teenage daughters, develop a theory that Jessup has killed before, but are unable to investigate fully for fear of blowing the police's cover.
Legal procedures require that the jury is kept ignorant of Jessup's history. Testimony given in the original trial, where the witness is no longer available because of death or informity, has to be read out by Harry Bosch. The defense attempts to undermine the testimmony of Sarah Gleason, who has a history of drug use and prostitution in the years since her sister's murder, though she has now been entirely rehabilitated. Bosch traces Sarah's former lover, Eddie Roman, and finds that he is still living off prostitute's earnings. Locating the prostitute Sonia Reyes, Bosch persuades her to enter the courtroom at a crucial moment in Roman's testimony, which causes the witness to alter his testimony, effectively destroying the defense case.
While anticipating a plea bargain from the defense team, Bosch and Haller hear that Jessup has entered Royce's offices with a gun and has killed Royce, two of his team and a policeman who was on his tail. Jessup is now at large and the police surround him at a hideout under the pier which had been discovered by Bosch as a result of the police surveillance activities. Jessup's death ends the search for Melissa Landy's killer, but leaves the prosecution team with a host of unanswered moral questions.
