In 1715, the Spanish galleon San Miguel is caught in a hurricane. Isabella Rojas and her six children desperately pray to God as black water rushes across the wooden decks. She binds each child to a ktted rope before being swept overboard. Each child drowns, their weight finally pulling Isabella beneath the stormy seas where they rest, waiting to be released from their watery graves. Over 200 years later, sixteen-year-old Marc encounters the ghost of Isabella while surfing. Along with Sponge Bob, a retired treasure hunter, they try to solve Isabella's legend. Then a tragic loss forces Marc to face his reality, as he discovers the secret treasure that he's been searching for all along.