A veteran New York Times reporter, now the Times' diplomatic correspondent in Europe, has pieced together one of the great shadowy stories of the Cold War: the exchange of East German prisoners (some of whom were accused of being spies) for West German funds, with the master mediator on the eastern side the nattily dressed lawyer, Wolfgang Vogel. His first major role was to arrange for the swap of U-2 pilot Gary Powers for Soviet spy Rudolf Abel. On the basis of many interviews and wide reading, Whitney reconstructs the story of Vogel's career, which began in the 1950s and gradually involved him as a central contact between the Stasi and the East German regime on the one hand and West German government leaders and church organizations on the other. The book is at once a thriller, a piece of contemporary history, and a judicious, sensitive guide through the morally complex world of the Cold War, where the East Germans collected some three billion Deutsche mark for freeing prisoners and where many East Germans lived in a gray zone, far from good and evil. Vogel, much decorated in the old G.D.R., well-connected in the F.R.G. before the fall of the wall, was himself briefly imprisoned after unification. Whitney fishes facts from Cold War mystery and in the process illuminates the feats and failures of the overblown intelligence industry and the atmosphere of the Cold War.