After barely escaping by hiding in the fog itself, the Surprise hobbles to a nearby shoal, where Captain Aubrey intends to put his ship back into action. Aubrey pursues the Acheron around "the Horn" of South America. His best friend, however, Stephen Maturin, the ships surgeon played by Paul Bettany, begins to question whether Jack has not become obsessed with defeating the superior ship and her sneaky, resourceful captain.