Francis Bright is a twelve-year-old boy living in sixteenth century England. Six months after his older brother's mysterious disappearance, Francis stumbles upon a clue which might reveal what really happened. As everyone around him questions his find, Francis is stolen away by the notorious Brotherhood of Blood and taken aboard a ship bound for the high seas. With the duplicitous Royal Navy fast on their trail, and the Spanish Armada conspiring with his murderous captors, Francis discovers that he is the key to unlocking the biggest mystery of all - a nine thousand-year-old riddle named Atlantis.