Decorated American submarine commander Eugene Fluckey, determined to go out with a bang, defies expectations and returns to USS Barb for one last patrol. On the eastern coast of Northern Japan, Fluckey and his crew push the boundaries of submarine warfare to new limits by launching rockets from their sub and landing a crew of saboteurs on Japanese land in order to destroy a coastal rail line. It's a highly aggressive and ambitious patrol that will forever change the way subs are used in battle.

In the icy waters off of Norway in 1945, a U-boat embarks on a mission to bring top-secret German technology to Japan, unaware that a Royal Navy V-class submarine has just been ordered to patrol the area. Neither commander manning their vessel realizes that they are about to face-off in the world's first underwater submarine dogfight. Witness the historic battle between HMS Venturer and U-864.

USS Silversides and its swashbuckling skipper, Creed Burlingame, saw their first action in the Pacific in May 1942. More than a dozen patrols later, the sub now rests in Muskegon, Michigan as a museum, an ongoing testament to its extraordinary history. Witness one of Silversides' most dramatic missions: aiding Marines in Guadalcanal by keeping Japanese reinforcements from reaching the island. It's an assignment fraught with depth charge attacks and aerial bombardments that nearly ended the mission and its crew.

German U-515 departs from France in 1944, bound for the African Gold Coast to hunt Allied ships. One thousand miles to the south, the U.S. Navy launches a new hunter-killer task force--a tactical combination of destroyers, escorts, carriers, and aircraft--to prevent German U-Boat resurgence. Witness the showdown between U-boat ace Werner Henke and U.S. Navy Bronze Star recipient Daniel Gallery and see how the unrelenting attack of hunter-killer groups changed how the Battle of the Atlantic was fought and won.

It was the most frightening moment of the Cold War: a crisis in Cuba in 1962 that brought the world to the brink of disaster. At the center of the drama are four Soviet submarines on a mission to supply nuclear torpedoes to bases on the communist island and the U.S. Navy hunter-killer group determined to turn the vessels around. Discover how grave miscommunications and fervent emotions could have led to catastrophe and the critical role played by the Second in Command aboard Soviet sub B-59.

It's 1941 and Erwin Rommel and his armies hope to take Egypt, gain control of the Suez Canal, and prevent Britain from receiving vital supplies from the colony of India and the Middle East. The Allies' last line of defense is a fleet of small, British U-class subs stationed on the tiny island of Malta. Despite unpredictable weather and a broken gyrocompass, HMS Upholder and its Lieutenant-Commander Malcolm Wanklyn battle to hold the line against the Axis powers and turn the tide of the North African Campaign.