Just days after the 9-11 attacks, a senior Pentagon analyst eased her red Toyota Echo into traffic and headed to work. She never saw the undercover cars tracking her every turn. As she settled into her cubicle on the 6th floor of the Defense Intelligence Agency in Washington, FBI Agents and twitchy DIA officers were hiding in nearby offices. For this was the day that Ana Montes--the US Intelligence Community superstar who had just won a prestigious fellowship at the CIA--was to be arrested and publicly exposed as a secret agent for Cuba.

Like spies Aldrich Ames and Robert Hanssen before her, Ana Montes blindsided her colleagues with brazen acts of treason. For nearly 17 years, Montes succeeded in two high-stress jobs. By day, she was one of the government’s top Cuba experts, a buttoned-down GS-14 with shockingly easy access to classified documents. By night, she was on the clock for Fidel Castro, listening to coded messages over shortwave radio, passing US secrets to handlers in local restaurants, and slipping into Havana wearing a wig.

Montes didn’t just deceive her country. Her betrayal was intensely personal. Her mercurial father was a former US Army Colonel. Her brother and sister-in-law were FBI Special Agents. And her only sister, Lucy, also worked her entire career for the Bureau. The highlight of her distinguished 31 years as a Miami-based language specialist: Helping the FBI flush Cuban spies out of the United States. Little did Lucy or her family know that the greatest Cuban spy of all was sitting right next to them at Thanksgivings, baptisms, and weddings.

In Code Name Blue Wren, investigative journalist Jim Popkin weaves the tale of two sisters who chose two very different paths, plus the unsung heroes who had to fight to bring Ana to justice. With exclusive access to a “Secret” CIA behavioral profile of Ana, family memoirs, and Ana’s incriminating letters from prison, Popkin reveals the making of a traitor—a woman labelled “one of the most damaging spies in U.S. history” by America’s top counter-intelligence official.

After more than two decades in federal prison, Montes will be freed in January 2023. Code Name Blue Wren is a thrilling detective tale, an insider’s look at the clandestine world of espionage, and an intimate exploration of the dark side of betrayal.