Stalin's Secret War: Soviet Counterintelligence Against the Nazis, 1941-1945 by Robert W. Stephan

The author does an excellent job with this book. Descriptions of various Soviet operations, what happened during and the outcomes are all written out and described with details and excellent sources. The reader will see that the myth that all Soviet POW's who were either liberated or escaped back to their lines from encirclements or German POW camps were sent to Gulag labor camps is a lie. After thorough checking by the NKVD the majority, 90% or more, were sent back to their units or used in another form at the front or in the rear, only around 10% were put into Penal battalions and companies or sent to Gulag camps because of various reasons.

An excellent section on how the Germans tried to penetrate the Red Army and NKVD by using POW's and others, the sheer volume of the amount of agents the Germans sent through Soviet front lines will give rise to an understanding that the NKVD had to be thorough in their jobs and many of those who did return might in fact have been working for the Germans in one way or another. All in all an excellent piece of literature on the time period and a great addition to our understanding of what went on during this war on the Eastern Front. As a comment to the other reviewer, the Soviets did not need to crack the German 'Enigma' codes, they had spies in top levels of the US and British secret services and through them received all the knowledge they needed about German activities. Sometimes British and US agencies shared information with the USSR and the NKVD or GRU (military intelligence) would then double check that information from their own spies in the respective agencies.