One of the most ambitious shipwreck searches ever undertaken was the hunt for two World War II battleships, now resting three miles beneath the sea. The British battle cruiser HMS Hood and German flagship Bismarck sank more than 60 years ago, with a combined loss of more than 3,000 men. Overcoming gales and equipment breakdowns, the searchers used unique satellite technology to send back the first images of the wreck of the Hood.