Operating alone and unarmed on the bottom of the sea, the U.S. Navy's smallest nuclear-powered submarine is one of its biggest weapons. Tied up at a pier, the boat with the bright orange sail looks absolutely minuscule, innocent and out of place beside its big brothers, the fleet's huge missile-carrying and attack submarines, but it can dive deeper, stay down for a month, and accomplish missions far beyond the capabilities of any of them. The ship has been cloaked in mystery. It wasn't commissioned or given a name, and even today it is hardly known beyond a select fraternity of sailors and scientists. They simply call it the NR-1. The little submarine was born in controversy, served in secrecy, survived potential catastrophe on numerous occasions, and is still in operation almost forty years after being conceived. It was and remains the only one of its kind ever built. The story of the NR-1 is told against the tense background of the Cold War and peopled with such rich characters as the acerbic Admiral Hyman Rickover, ocean scientist Robert Ballard (who found the Titanic), the designers and builders who faced almost impossible tasks to give life to the ship, the unique officers and sailors who took the little boat down into depths on covert missions, and the families who waited for them on shore, unaware that there would be no escape if the boat ran into trouble. Dark Waters: An Insider's Account of the NR-1, the Cold War's Undercover Nuclear Sub is a thrill-a-minute book of submarine adventure, imminent danger, personal bravery, technological wonder and historic discovery. It will be a proud addition to the shelves of readers who love stories of the sea, history and intrigue.