The Black Echo recap

A body in a drainage pipe draws LAPD detective Harry Bosch back to his service as a Vietnam tunnel soldier when he identifies the dead man as former comrade Billy Meadows. Signs that the apparent overdose was staged connect the death to a sophisticated bank-vault burglary carried out through Los Angeles tunnels. Bosch works uneasily with FBI agent Eleanor Wish while Internal Affairs watches him and more witnesses are placed in danger. The inquiry moves from veterans of the tunnel units to the people who knew confidential details of the robbery investigation. Bosch ultimately enters the underground route and breaks up a second operation. He learns that trusted participants on the investigative side helped plan the crimes and silence Meadows. One dies in the confrontation; another confesses and goes to prison. The murder is solved, but Bosch's growing personal attachment to Wish is destroyed by the truth.

Harry Bosch is called to a body in a drainage pipe near Mulholland Dam. Patrol officers assume the dead man overdosed, but Bosch notices signs that the scene has been arranged. He recognizes the victim as Billy Meadows, a fellow member of a Vietnam tunnel unit who later became addicted to heroin. The personal connection gives Bosch another reason to resist pressure for a quick disposition. As he and Jerry Edgar trace Meadows's last movements, Bosch learns that the dead man had recently possessed more money than his circumstances explained. His superiors, including Lieutenant Harvey Pounds and Irvin Irving, are already wary of Bosch's methods, while Internal Affairs detectives Lewis and Clarke begin covertly following him. What looks like a routine drug death becomes a homicide inquiry tied to Bosch's own past.

Evidence around Meadows points toward an earlier burglary in which thieves tunneled into a bank and opened selected safe-deposit boxes. Because the method resembles military tunnel work, Bosch sees a possible role for veterans with Meadows's training. The federal bank-robbery squad, represented by Eleanor Wish and John Rourke, protects its investigation and initially resists Bosch's intrusion. Bosch and Wish nevertheless begin comparing the homicide evidence with the still-unsolved theft. A teenager called Sharkey may have seen activity near the place where Meadows was left, but he is frightened and unreliable. The parallel police and FBI inquiries now share suspects, methods, and an underground geography.

Bosch and Wish follow the connections among Meadows, other former tunnel soldiers, and the bank job. Technical details show that the thieves understood both underground construction and the authorities' response. Bosch's refusal to stay within departmental boundaries intensifies the Internal Affairs surveillance. He and Wish also grow personally close, although each continues holding back parts of the past. Sharkey's knowledge makes him increasingly exposed; when he is killed, the case demonstrates that the people behind the tunnel operation are still active and willing to remove witnesses. Bosch concludes that the original burglary was not an isolated event and begins looking for the next target.

The investigation narrows around a fresh underground route and valuables held in another secured location. Bosch uses what he remembers from Vietnam to understand how the team will move, ventilate its passage, and control anyone who reaches it. The killers appear to know investigative information that should be confined to law enforcement, forcing Bosch to consider an insider without yet knowing where the breach lies. Lewis and Clarke's surveillance complicates his movements and creates a second danger around the operation. Bosch and Wish prepare to enter the tunnels rather than wait for the thieves to emerge, aware that the enclosed space favors people trained for it.

Bosch and Wish move toward the active tunnel as the robbery team puts its plan into motion. The route, equipment, and timing confirm that Meadows was part of a practiced group and that his death followed a breakdown in trust among its members. Above ground, the overlapping LAPD, FBI, and Internal Affairs operations create confusion about who has reliable information. Underground, Bosch is forced to rely on skills he had hoped to leave in Vietnam. The case has become a contest over who can reach the vault and escape route first, while the identity of the person directing the thieves remains unresolved.

Inside the tunnel system, Bosch discovers that FBI agent John Rourke has been directing the burglary conspiracy and killing participants who threatened to expose it, including Billy Meadows. Rourke attempts to eliminate Bosch but dies in the underground confrontation, ending the immediate operation. Eleanor Wish then reveals her own knowing part in the scheme. Her motive was bound to her brother's death in Vietnam and to the valuables selected from the vault, but she accepts that this does not excuse the crimes. Wish surrenders and is sent to prison. Bosch closes Meadows's murder and emerges from the Internal Affairs pressure, yet his trust in Wish and the relationship developing between them are finished. The epilogue leaves him alive and vindicated on the case, but isolated by what solving it required him to learn.

Bosch and Wish enter the storm-drain system as the burglary plan reaches its end. FBI agent John Rourke is exposed as the insider who directed the operation and eliminated people who could connect him to it, including Billy Meadows. Rourke tries to kill Bosch underground but dies during the confrontation. Wish then admits that she knowingly took part in the scheme: the targeted vault held valuables tied to men she blamed for her brother's death in Vietnam, and her alliance with Bosch did not erase her role in the crimes. She surrenders and is imprisoned. Bosch solves Meadows's murder and survives both the tunnel and Internal Affairs scrutiny, but the relationship he had begun with Wish ends with her confession. The case leaves him facing the cost of pursuing truth when the people closest to the investigation have concealed the most important facts.