When a miner finds a rich vein of ore, he mines it as long as he can. The same is true in any area of study or exploration. Fortunately for students of the Second World War, Patrick O’Donnell discovered the rich and largely untapped tales of the OSS. Last year, O’Donnell delivered the riveting The Brenner Assignment: The Untold Story of the Most Daring Spy Mission of World War II. This year, he has given us the equaling compelling They Dared Return: The Untold Story of Jewish Spies Behind the Lines in Nazi Germany (forthcoming from Da Capo Press, November 2009; 256 pages). In They Dared Return, O’Donnell traces the stories of five Jewish friends who had escaped from Europe and who were later chosen by the OSS to infiltrate German territory in the final months of the war. Remarkably, these men were placed into small groups which included former German soldiers who had agreed to assist the allies. The teams were then dropped into the Alpine region of Austria so that they could gather information on, among other things, the rumored Alpine redoubt that Hitler was allegedly developing as a final defensive position for the soldiers of his Reich. They Dared Return grew out of O’Donnell’s conversations over eight years with Fred Mayer, one of the five Jewish OSS agents featured in the book. Mayer’s story, like that of so many people who fought against Fascism during WWII, is at times horrific and always awe-inspiring. Although Mayer’s father had been a hero during the Great War, his family was still subject to the anti-Semitism that destroyed Europe in the 1930’s. After years of bureaucratic hassles, Mayer’s father was finally able to obtain visas for his family to immigrate to the United States in 1940. About two years later, twenty year old Fred Mayer was in the Rangers. Soon thereafter, he was recruited to the OSS. Mayer’s story in the OSS is the kind of edge-of-your-seat adventure that certainly must have inspired and influenced Ian Fleming in his creation of the James Bond character. After going through interminable delays before finally getting the go-ahead for his mission, Mayer would spend the last few months of the war engaged in covert operations in and around Innsbruck, Austria. Disguised as either a French worker or a German soldier, Mayer infiltrated the German infrastructure of Innsbruck and relayed much information back to OSS headquarters in Italy. Eventually captured and tortured, Mayer was spared further torture or possible death when another OSS operative (a German deserter who volunteered for OSS duty) suggested to his captors that Mayer was an important general in the US Army. Not wanting to incur the anger of such a high ranking American officer during the final days of the war, Mayer’s captors greatly eased the terms of his confinement. The most remarkable aspect of Mayer’s time in Austria came shortly before the Americans advanced on Innsbruck. Having been released from his captivity, Mayer persuaded the Nazi governor of the Innsbruck area to surrender without resistance in order to spare more lives and the city of Innsbruck itself. They Dared Return offers a glimpse into the stories of both European Jews who volunteered to return to their homelands to help eradicate the scourge of Nazism. It is also, however, the story of German soldiers who recognized that their country was not worthy of their loyalty in the face of so many atrocities. They, too, willingly returned to fight against their own people. Both the Jews and the deserters who returned to fight have stories worth hearing. Although They Dared Return can at times be difficult to follow, as O’Donnell moves back and forth from one mission to another, on the whole it is a wonderful addition to the recent burst of scholarship surrounding Southern Europe during World War II. In many ways, it reads as a sequel to The Brenner Assignment and readers will enjoy the overlap among characters and experience that are relayed in both books. Moreover, any reader of O’Donnell’s cannot help but feel that all of his histories are ready to be made into films, and readers can only hope that Hollywood pays heed to that call. They Dared Return will engage novice and expert students of World War II alike. It is a fine book.