Hell Below

American submarines risk everything to surface in enemy waters and rescue downed aviators.

A German U-Boat Commander makes an unprecedented voyage to attack Allied shipping off the coast of Australia on Christmas morning.

An American submarine commander risks everything in a fight from within an enemy convoy.

A German U-boat commander launches a shocking attack at the heart of the Royal Navy.

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.

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.

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.

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.

A Nazi U-boat heading back for repairs unintentionally cruises right into the middle of a large Allied convoy on March 16, 1943. It is a lucky accident that sets the stage for the largest convoy battle of World War II. Relive this momentous chapter in the war for the Atlantic, an intense game of chess pitting Admiral Karl Donitz's wolf pack against a battered British Navy. It's a three-day showdown with unparalleled violence and unexpected outcomes that will turn the tide of the war.

Just one month after the Japanese attack on Pearl Harbor, another enemy brought World War II to American shores, not through the air but beneath the sea. This is the story of Operation Drumbeat, German Admiral Karl Donitz's campaign to send U-boats to the doorstep of the U.S. and attack Allied merchant shipping from Newfoundland to North Carolina. Through archival war footage and military expert testimony, we reveal how the Nazis managed to hammer our coast again and again and why the U.S. Navy was unable to stop them.

The wolfpack tactic was made famous by Admiral Karl Donitz, Hitler's mastermind of submariners. His strategy: to send teams of U-boats to bear against the convoys of ships heading from Canada to Britain, cut maritime lifelines, and starve the enemy into defeat. Take a deep dive into the North Atlantic as we go above and below sea level to relive one of the first attacks of Donitz's lethal subs in 1940, headed by leader of the pack Commander Otto Kretschmer. Then follow Britain's war strategists as they race to combat this new deadly attack.

The USS Harder, led by Commander Sam Dealey, sank multiple Japanese destroyers, rescued Allied operatives from capture in Borneo, and outmatched many rival ships and aircraft to return home. And that was during just one patrol. Take a deep dive aboard this submarine as we relive this incredible war patrol in the spring of 1944, and witness the events that accelerated the campaign against the Japanese and earned Dealey the Medal of Honor.