Gray Day

A cybersecurity expert and former FBI 'ghost' tells the thrilling story of how he helped take down notorious FBI mole Robert Hanssen, the first Russian cyber spy. 'Both a real-life, tension-packed thriller and a persuasive argument for traditional intelligence work in the information age.'--Bruce Schneier, New York Times bestselling author of Data and Goliath and Click Here to Kill Everybody Eric O'Neill was only twenty-six when he was tapped for the case of a lifetime: a one-on-one undercover investigation of the FBI's top target, a man suspected of spying for the Russians for nearly two decades, giving up nuclear secrets, compromising intelligence, and betraying US assets. With zero training in face-to-face investigation, O'Neill found himself in a windowless, high-security office in the newly formed Information Assurance Section, tasked officially with helping the FBI secure its outdated computer system against hackers and spies--and unofficially with collecting evidence against