After a difficult rounding of Cape Horn, the expedition reaches San Patricio in Chile. "Ringle" goes for repairs following a grounding in the Pillón passage. After a meeting between Aubrey, Maturin and Sir David Lindsay, in which the two sides agree to mutually support each other, Maturin writes to Blaine describing the different juntas and the training of three republican sloops by the crew of the "Surprise", who assist in capturing a moderate privateer. After meeting Dr Jacob with the intelligence he gathered, Aubrey heads to Valparaiso, while Maturin and Jacob ride there by mule. Here they meet General Bernardo O'Higgins, the Supreme Director, and Colonel Eduardo Valdes. Learning that the viceroy of Peru, under the Spanish king, plans to invade Chile, the group determine to confront the Royalist forces at Valdivia, where the viceroy will need to seek stores. The "Surprise" and "Ringle" make sail and Aubrey elaborates a plan to drop Chilean troops at Concepción while the ships destroy the gun-emplacements at Cala Alta and then bombard the fort at Valdivia.