Jeffery Deaver. The Blue Nowhere (2001) 426 pp.
A sadistic computer hacker, code-named Phate, sets his sights on Silicon Valley, infiltrating his victims’ computers, invading their lives, and luring them to their deaths. An imprisoned hacker named Wyatt Gillette is freed to aid in the investigation, and teams up with old-school homicide cop Frank Bishop, forming an uneasy alliance in which they must utilize every ounce of their respective talents to stop Phate.