In 2004, a California computer whiz named Barrett Lyon uncovered the identity of a hacker running major assaults on business websites. Without fully grasping the repercussions, he set on an investigation that led him into the heart of the Russian mob. Cybercrime was evolving. No longer the domain of small-time thieves, it had been discovered by sophisticated gangs. They began by attacking corporate websites but increasingly stole financial data from consumers and defense secrets from governments. While Barrett investigated the cutting edge of technology crime, the U.S. government struggled to catch up. Britain, however, was a different story. In the late 1990s, the Queen herself had declared safe e-commerce a national security priority. Agents from the London-based National Hi-Tech Crime Unit sought out Barrett and enlisted his help. They also sent detective Andrew Crocker, a Welsh former boxer, to Russia to track down and prosecute the hackers—and to find out who they worked for. Fatal System Error penetrates both the Russian cyber-mob and the American mafia as the two fight over the Internet’s massive spoils. It takes readers into the murky hacker underground, traveling the globe from San Francisco to Costa Rica, London, and Russia. Using unprecedented access to mob businesses and Russian officials, it shows how top criminals earned protection from the Russian government—and how Barrett Lyon and Andrew Crocker got closer to the titans of the underground economy than any previous outsider. Together, their stories explain why cybercrime is much worse than you thought—and why the Internet might not survive.