It is 1702, and in the lawless Caribbean sea young Matthew Loftus determines to captain his ship, the Cornelius, by honest trade rather than piracy and plunder. But his crew is discontent, and lusts after the spoils that their fast, well-armed ship can win, and even his love, Abigail, doubts him.On the run from a charge of mutiny, Matthew sees a chance to win himself a pardon when he learns of a secret almanac that advances the science of navigation. He embarks on the cause of solving the Longitude. But is the almanac what it seems? Pursued by unprincipled merchants, duplicitous privateers and the English Navy, Matthew struggles with navigational uncertainties and his own reversals of fortune. Through gales and sea battles, he sails his beloved schooner towards the great goal he has set himself.