The ghost and the mole; Eric O'Neill's Gray Day. [Special Editions]

Eric O’Neill is a former FBI counterintelligence and counterterrorism operative, and founder of the Georgetown Group, a security and investigative firm, as well as national security strategist for Carbon Black. In his book Gray Day, My Undercover Mission to Expose America’s First Cyber Spy, Eric O’Neil shares the fascinating and sometimes harrowing tale of his experience being assigned to help expose Robert Hanssen, the FBI’s most notorious mole. In 2001 Hanssen pleaded guilty to multiple charges of espionage for sharing classified information with the Soviet Union and Russia over the course of over two decades.