1939, Berlin, Cambridge, Paris, California. The world is in the grips of a terrible war. Can two young women change the course of history? As war is declared in Europe, shy young Judy Morgan finishes her studies in Physics at Cambridge University. She never thought she’d be friends with someone as beautiful and glamorous as Hedy Lamarr, a young Jewish woman who has fled the Nazis, but Judy can’t ignore her brilliance. It is a time when women are expected to stay at home, but as bombs tear apart the country she loves, Judy knows she must act. With Judy’s unparalleled knowledge of how the world works, and Hedy’s flair for invention, Judy is sure they can find a way to keep their loved ones safe. But in war, impossible decisions must be made, unthinkable sacrifices must be suffered, and their work puts them in grave danger. As they journey down a dark, uncertain path together, Judy realises her next step could tear their friendship apart. But the fate of the world is in her hands. Tragedy is inevitable, but can Judy solve the puzzle she has set herself, save millions, and put an end to this terrible war? Fans of The Nightingale and Beneath a Scarlet Sky will love this unputdownable, heartbreaking but uplifting novel. Based on two true stories of amazing ‘hidden women’ who altered the fate of the Second World War, this unforgettable novel about extraordinary courage, love and sacrifice proves the power of friendship even in the darkest hours of history.