Just days before Germany invaded the Soviet Union on 22 June 1941, Stalin refused to believe the detailed - and correct - intelligence from his own security agencies that the attack was imminent. He dismissed the urgings of his generals to take steps to safeguard the Russian homeland. Stalin's catastrophic blunder proved costly: his failure to act ultimately led to the deaths of millions. This book is the first to bring out of the shadows the intelligence war between Hitler and Stalin during the years 1939 to 1941. Drawing on extensive Soviet archival material, much of it newly released, David Murphy presents abundant information about Stalin's world, his relations with his Kremlin colleagues and many enigmas that have surrounded the Nazi invasion. Of particular interest, Murphy uncovers two previously unknown letters from Hitler to Stalin in which the German leader asserts that Germany will never invade the Soviet Union. With documented revelations about what Stalin knew and complex analysis of how he thought, Murphy provides an unparalleled portrait of the mind of the dictator and the workings of the system over which he presided.