Hotspur reconnoiters the approaches to the French naval base of Brest, and narrowly avoids capture when war is declared. Once the British fleet blockades Brest, Hornblower's restlessness and perfectionism prompts him to lead attacks and landing parties. In spite of gaining a good reputation, Hornblower makes no financial profit from his activities. When Admiral William Cornwallis tries to put him in a position where he can make easy prize money by capturing a large shipment of Spanish gold, he instead takes on a stronger enemy frigate sent to warn the convoy and keeps it from accomplishing its mission.

Eventually, by superior seamanship and skill, he drives it away. Hornblower rationalises that this is poetic justice, after he had earlier connived to facilitate the escape of his steward, who was facing hanging for striking a superior officer (a punishment Hornblower could not abide). It later transpires that the prize ships were claimed by the Admiralty (Droits of Admiralty), as war had not been officially declared against Spain at the time of the capture, so Hornblower would not have profited in any case.