On 25 January 1917, HMS Laurentic struck two German mines off the coast of Ireland and sank. The ship was carrying 44 tons of gold bullion to the still-neutral United States in order to finance the war effort for Britain and its allies. Britain desperately needed that sunken treasure, but any salvage had to be secret since the British government dared not alert the Germans to the presence of the gold. Lieutenant Commander Guybon Damant was the most qualified officer to head the risky mission. Wild gales turned the operation into a multiyear struggle of man versus nature. As the war raged on,...