I’ve read most of the Bosch books.

Black Echo is the 1992 début novel by American crime author Michael Connelly. … won the Mystery Writers of America Edgar Award for “Best First Novel” in 1992.

Detective Hieronymus “Harry” Bosch …

… debuted as the lead character in the 1992 novel The Black Echo, the first in a best-selling police procedural series now numbering 21 novels. …

Bosch’s mother was a prostitute in Hollywood who was murdered on October 28, 1961, when Bosch was 11 years old. …

In Vietnam, Bosch was a “tunnel rat” (nicknamed “Hari Kari Bosch”), with the 1st Infantry Division—a specialized soldier whose job it was to go into the maze of tunnels used as barracks, hospitals, and on some occasions, morgues, by the Vietcong and North Vietnamese Army. …

After his return from Vietnam and an honorable discharge from the Army, Bosch joined the LAPD …

Harry is astonishingly unchanged from the beginning nearly 30 years ago.

Titus Welliver in the TV series is quite true to fiction. Season 3 of the Amazon TV series, Bosch, is loosely adapted from this novel.