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Hell Below

They traveled alone and in packs. They collected intelligence and launched attacks. They rose above the ocean depths and ultimately changed the course of war. Chart some of the most dramatic and influential submarine patrols of World War II, from the perspective of the naval masterminds who plotted the strategies to the tenacious and aggressive commanders who carried them out. Follow the ongoing challenges the Axis and Allies faced as they pushed the limits of their vessels in pursuit or in escape.

Part 4 Atlantic Showdown

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.

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