The Black Echo

For LAPD homicide cop Harry Bosch — hero, maverick, nighthawk — the body in the drainpipe at Mulholland dam is more than another anonymous statistic.  This one is personal.
The dead man, Billy Meadows, was a fellow Vietnam "tunnel rat" who fought side by side with him in a nightmare underground war that brought them to the depths of hell.  Now, Bosch is about to relive the horrors of Nam.  From a dangerous maze of blind alleys to a daring criminal heist beneath the city to the tortuous link that must be uncovered, his survival instincts will once again be tested to their limit.