This inside account of the investigation that led to her arrest has been written by Scott W. Carmichael, the DIA's senior counterintelligence investigator who persuaded the FBI to launch an investigation. Although Montes did not fit the FBI's profile of a spy and easily managed to defeat the agency's polygraph exams, Carmichael became suspicious of her activities and with the FBI over a period of several years developed a solid case against her. Here he tells the story of that long and ultimately successful spy hunt. Carmichael reveals the details of their efforts to bring her to justice, offering readers a front-row seat for the first major U.S. espionage case of the twentieth century. She was arrested less than twenty-four hours before learning details of the U.S. plan to invade Afghanistan post-September 11. Motivated by ideology not money, Montes was one of the last "true believers" of the communist era. Because her arrest came just ten days after 9/11, it went largely unnoticed by the American public. This book calls attention to the grave damage Montes inflicted on U.S. security--Carmichael even implicates her in the death of a Green Beret fighting Cuban-backed insurgents in El Salvador--and the damage she would have continued to inflict had she not been caught.