In 1807, Captain Horatio Hornblower leads his ship the HMS Lydia on a perilous voyage around Cape Horn and into the Pacific. The men, even his officers, don't know exactly where he is leading them. England is at war with Napoleon and everyone wonders why they have been sent so far from the action. They eventually arrive on the Pacific coast of Central America where the HMS Lydia has been sent to arm Don Julian Alvarado, who is planning an attack against France's Spanish allies on the North American continent. The hope is that Alvarado's forces will require the French to divert some of their military resources to North American defense in the aid of their Spanish allies. He arrives to learn that a Spanish Galleon is en route and he no sooner captures it and hands it over to Alvarado that he learns the Spanish are now England's allies and he must take it from Alvarado. He also gets a very comely passenger in the form of Lady Barbara Wellesley, sister of the Duke of Wellington. The voyage is uneventful but Horatio and Barbara develop a deep affection for one another, despite that he is married and she is engaged. There are more battles ahead however for Hornblower and he finds himself under the command of Admiral Leighton, Barbara's new husband.