The War of 1812 continues, and Captain Jack Aubrey sets course for Cape Horn on a mission after his own heart: intercepting a powerful American frigate outward bound to wreak havoc with the British whaling trade. Meanwhile, Stephen Maturin has a mission of his own in the world of secret intelligence and comes face to face with the harsh realities for women of the age. Disaster in various guises awaits them in the Great South Sea and in the far reaches of the Pacific-typhoons, castaways, shipwrecks, an ill-fated affair, murder, and criminal insanity-as well as a bold rescue by a crew of seafaring female warriors.