The Fourth Man

"In the aftermath of the Cold War, American intelligence caught three high-profiles Russian spies: Aldrich Ames, Edward Lee Howard, and Robert Hanssen. However, rumors have long swirled of another mole, often referred to as the Fourth Man. Former CIA operative Robert Baer tells the full story of the CIA investigation launched after the Ames arrest to make sure there wasn't another mole in their ranks"--Publisher's description.