The story begins with "Surprise" in the Strait of Magellan, caught up in foul weather. Hanson first spots Cape Pilar at the very opening of the Strait, and soon "Surprise" moors and conducts some trade with the inhospitable locals for meat and vegetables. Having re-provisioned, she and "Ringle" sail northwards in fine weather until they enter the River Plate and moor close to the island functioning as the main administrative centre. A quarantine officer comes aboard and gives the frigate a clean bill of health.