On the eve of WWII, scientists across the globe – in Germany, Britain, America and France, among others – came to the realization that splitting the atom could bring enormous power. So began the race to develop an atomic bomb, a power so great that entire cities could be destroyed in an instant with a single weapon. Ironically, for most of the decade, a Norwegian hydroelectric plant at Vemork had been using a hugely expensive process to produce minute quantities of a fluid for which there was no practical, commercial purpose. However, physicists had expressed interest in using it in experiments. That substance, called deuterium or more commonly “heavy water,” turned out to be a vital component of the process to creating Uranium 235. Scientists in both Germany and America posited that this isotope could the most likely way to create atomic fission, splitting an atom and thereby releasing a massive burst of energy. So when the Nazis occupied Norway, they came to possess this invaluable and then-unique source of heavy water supplies, gaining an important advantage in the development of an atomic weapon. THE WINTER FORTRESS is the story of the effort by Norwegian patriots, trained and equipped by the British, to destroy the Vemork plant’s heavy water production. In the dead of winter in one of Norway’s most inhospitable regions, nine men faced hundreds of crack German troops in what was considered a suicide mission to slow or even destroy the heavy water production. The Norwegian commandoes knew the outcome of the war itself could depend on the success of their mission. This is a riveting tale, told in a face-paced, richly researched volume that makes plain the sacrifices of war in a small, albeit important, corner of the greatest conflict in the history of mankind.