With the Doomsday Clock the closest it's ever been to midnight, Jane Corbin investigates the proliferation of nuclear weapons across the globe. She visits Los Alamos, home to the United States' nuclear weapons development facility and the historic home of Oppenheimer's Manhattan Project, and also Scotland, where she reveals the strategy behind Britain's nuclear deterrent. This is a story told by the scientists, investigators and diplomats who set the clock and have fought to ensure that the ultimate deterrent has not been used in over 70 years. Show less