Mel Fisher and his handpicked team were armed with advanced electronic equipment and mechanical devices of their own invention, revolutionizing the techniques for underwater search and salvage. With this equipment and knowledge gained while salvaging the 1715 fleet ships, Fisher and his group realized it was possible to search for specific shipwrecks with a reasonable expectation for success.

In 1966, stimulated by their success on the 1715 fleet ships, the group headed for the Florida Keys where they expected to find their next targets- the legendary Nuestra Senora de Atocha and Santa Margarita, lost galleons of the 1622 Spanish Fleet. These two ships were renowned for immense wealth in their cargo holds when they sunk, a wealth that remained hidden at the bottom of the ocean.