Bosch is trying to solve cold cases as a volunteer for the San Fernando police department when he is tasked with helping the town's three inexperienced detectives at the scene of a crime, a store where two pharmacists, a father and son, have been shot dead.

The evidence at the chemist leads them into the big business world of prescription drug abuse, propelling Bosch upon a dangerous mission to snare the head of a highly organised criminal empire.

At the same time, an old case from his days with the Los Angeles Police Department comes back to haunt him, threatening to ruin his reputation and leave him unable to provide for his daughter Maddie.

A long-imprisoned killer claims Bosch framed him. The allegation is supported by the discovery of new evidence on clothing stored in sealed boxes at a secure police compound since the murder trial.

After leaving the LAPD on bad terms, the gruff detective cannot rely on his former employer to protect him from a public accusation of planting evidence at a crime scene or from a ruinous civil compensation claim for false imprisonment.

Bosch must call on years of experience and the slick skills of his half-brother Mickey Haller, "The Lincoln Lawyer", to clear his name and keep a clever killer in prison before an assistant district attorney who is keen to throw him to the wolves quashes the murder conviction.

It is testament to Connelly's skill as a storyteller that the 20th novel in this bestselling series still feels fresh and relevant. The world-weary yet tough Bosch has been given a new lease of life in retirement and the reader shares his sadness at flaws in the justice system.

With Haller providing lightness and humour against Bosch's grit and determination, Connelly's fans will cherish this gripping thriller.