'Is there a point beyond which the scientist cannot go under any circumstances?' - Heisenberg's uncertainty about nuclear progress. 'I am become Death, the destroyer of worlds' - Oppenheimer quoting the Bhagavad Gita after witnessing the successful demonstration of the atom bomb. The bomb which killed an estimated 140,000 (tbc) civilians in Hiroshima and destroyed the countryside for miles around, was one of the defining moments in world history, if not the defining moment of the twentieth century. That mushroom cloud cast a terrifying shadow over the contemporary world and continues to do so today. But how could this have happened? What led to the creation of a weapon of mass destruction on an unprecedented other-worldly scale? From the moment scientists contemplated the destructive potential of splitting the atom the role of science changed. Ethical and moral dilemmas faced all of those who realised the implications of their research and those who decided to use and advance it. BEFORE THE FALL-OUT charts the chain of events from Marie Curie's scientific breakthrough through the many colourful characters such as Einstein, Robert Oppenheimer, and Lord Rutherford whose discoveries contributed to the bomb. Many of the international scientists who had collaborated and developed close friendships in the early years of the century would find themselves on opposite sides of a world war with loyalties and motivations called into question. The fate of Jewish scientists in the field also hung in the balance with colleagues taking huge risks to rescue and find them positions abroad. In war-time, the arms race became a matter of covert undercover operations, the British Maud Committee competing with the German Uranium Club and even the American Manhattan Project. A complicated ballet of Anglo-American relations moved from co-operation to hostility, secrecy and independence. The story of the atomic bomb spans 50 years of prolific scientific innovation, turbulent politics, foreign affairs and world-changing history. Through personal stories of exile, indecision and soul-searching, to charges of collaboration, spying and deceit, Diana Preston presents the human side of an unstoppable programme with a lethal outcome.