The harrowing story of Mel Fisher's quest for the 600-ton galleon Nuestra Senora de Atocha, vice-flagship of King Philip IV of Spain, which sank off Key West in 1622, taking with it to the bottom 250,000 silver coins, 901-plus silver ingots, 161 pieces of gold bullion, emeralds and other jewels—47 tons of treasure in all, worth $600 million today, Fisher claimed. If he could find it. Trusting to incredible persistence, raw courage and luck, Fisher and his divers searched the reefs and seas for clues. They fought off storms and sharks. Salvage vessels sank under them. Four crewmen were killed. Years were spent making futile dives and arranging desperate deals for financial backing; divers never knew when or if they would be paid— whether they would live to see the end of the adventure at all. Mel Fisher, the incredible optimist who never gave up, cheered his crew each morning with his slogan, "Today's the day!"