Prior to the outbreak of the war the massive German chemicals conglomerate I.G. Farben - the future manufacturers of Zyklon-B, the gas used in the Nazi concentration camps - had started producing bulk supplies of deuterium oxide - heavy water - at the remote Norwegian plant of Vemork. This was the central target of three separate missions - Operations GROUSE, FRESHMAN and GUNNERSIDE - over the ensuing four years. As Churchill commented: 'The actual facts in many cases were equal to the most fantastic inventions of romance and melodrama. Tangle with tangle, plot and counter-plot, ruse and treachery, cross and double-cross, true agent, false agent, double agent, gold and steel, the bomb, the dagger and the firing party were interwoven in a texture so intricate as to be incredible yet true.'
Damien Lewis's bestseller intercuts the hunt for the scientists, the raw materials and the plant, with the cloak and dagger intelligence game being played in the shadows. This relied in part on ENIGMA intercepts to guide the SOE's hand. Lewis delves into some of the most extraordinarily inventive and Machiavellian innovations at the SOE, and their related research and training schools, whereby the enemy were tricked, deceived, framed, blackmailed and double and triple-crossed, all in the name of stopping the Reich from getting the bomb.