For over fifty years the world's two greatest superpowers, the United States and Soviet Union, pour their resources into a terrifying array of doomsday weapons and military machines. The Cold War is the world's first nuclear armed confrontation. Remarkably, it's also the greatest clandestine war in the history of mankind - conducted in secret beneath the waves. Now, with access to daring expeditions, precision data and classified information, we use ground-breaking computer-generated-images to drain the ocean and reveal the shocking secrets of the nuclear-armed Cold War.