At the height of World War II, Oak Ridge, Tennessee, was home to 75,000 residents, consuming more electricity than New York City. But to most of the world, the town did not exist. Thousands of civilians—many of them young women from small towns across America—were recruited to this secret city, enticed by solid wages and the promise of war- ending work. Kept very much in the dark, few would ever guess the true nature of the tasks they performed each day in the hulking factories in the middle of the Appalachian Mountains. That is, until the end of the war—when Oak Ridge’s secret was revealed.