This is the true story of unorthodox, underdog intelligence officers who fought an uphill battle against their government to prove that the KGB had pulled off the most devastating and breathtakingly thorough penetration of U.S. national security in history.

Incorporating declassified internal CIA memos and diplomatic cables, this suspenseful narrative reads like a thriller-but real lives were at stake, and every twist is true as the US and USSR attempt to wrongfoot each other in eavesdropping technology and tradecraft. The book also carries a chilling warning for the present: like the State and CIA officers who were certain their sweeps could detect any threat in Moscow, we don t know what we don t know.