From the tide-torn waters of the Thames, where Captain Nathaniel Drinkwater is compelled to handle a deserter, to the seas off Cape Horn, storm-scoured gateway to the Pacific, the great cruiser Patrician is tense with the threat of mutiny. Despite this, Drinkwater captures a Spanish frigate and meets the stunning Doña Ana Maria, daughter of the Commandante of San Francisco. But having disturbed a hornet's nest of colonial intrigue, Drinkwater finds that the Spanish are eager to humiliate him and the Royal Navy. Moreover, a Russian battleship lurks somewhere offshore, pursuing Tsar Alexander's dark plans. Caught between two formidable enemies, Drinkwater's mission is made impossible by treachery.

But chance brings the aid of Doña Ana Maria and a mysterious mountain man. In the distant waters of this beautiful and remote region, Drinkwater struggles to carry out his mission and is struck with the most extraordinary twist of fortune in his eventful life.