Diving for plunder in the Caribbean, Hector Lynch and his companions are spotted by a Spanish ship. Escaping capture by burning the vessel's sails - an act of piracy - they head for Tortuga, where Hector's wife Maria awaits. He longs for a better life for them both, on the right side of the law. But the crew run into Laurens de Graff - a renowned mercenary captain now in command of a royal French frigate - and after fleeing his clutches, they are cast away on a tiny desert island, Salt Tortuga. Hector tries desperately to make his way back to Maria, meanwhile she has decided to undertake the hazardous journey to find him....