The designer drug 'black ice' is leaving a bloody trail through the streets of Hollywood, and Harry Bosch is assigned to investigate the story's core case—the apparent suicide of a narc—despite warnings by top brass to lay off. As Bosch moves further into the case, he realizes that one of his open cases, the slaying of an unidentified Hispanic, seems to tie in to the death of the narc. His investigation picks up speed once Bosch heads down to Mexico, where he matches wits with corrupt cops, attends bullfights, breaks into the distribution center for Mexico's black-ice kingpin, and finally raids the kingpin's ranch.