Battle of the Atlantic: The U-Boat War

As German U-boats tighten their grip on the Atlantic, Allied losses mount and hope fades. Then a single captured submarine yields a working Enigma machine that could change the course of the war.

Nazi U-boats devastate Allied convoys across the Atlantic. As Royal Navy destroyers fight back at sea, a secret intelligence war unfolds at Buckinghamshire's "Spy House," where hidden listeners extract vital information from German POWs.

As D-Day approaches, Allied control of the Atlantic is vital. In May 1943, a massive U-boat force targets a convoy, triggering a brutal multi-day battle with the Royal Navy that helps decide the outcome of the Atlantic war.