Detective Harry Bosch learns the DA's office is examining new evidence which threatens to overturn an old case, potentially jeopardizing all of Bosch's other convictions. Meanwhile, a robbery turned murder at a local pharmacy exposes an opioid ring that drags Bosch down a dangerous path.

Bosch and Edgar uncover more details about the pharmacy murder and the opioid operation, while Detective Robertson works a tandem homicide. As Bosch pushes back against the deathbed confession at the heart of Borders' petition for release, he enlists the help of a longtime adversary. J. Edgar tries to persuade a former CI to cooperate with an investigation.