The Red Orchestra: The Soviet Spy Network Inside Nazi Europe (Cassell Military Classics)

It's a real-life spy story, straight from the heart of the Second World War. This triumph of espionage by the Soviet Military Intelligence took the Nazis over two years to crack. Made up of a diverse mixture of Russians, Jews, Poles, and other Europeans (including some Germans), the Red Orchestra played a vital role in the destruction of Nazism--despite the constant fear of discovery. Many were tortured. But, by the time the Germans finished their investigation, the Eastern front was already lost.