Before taking the Renown back to Jamaica for their court martial on charges of mutiny, Hornblower, Kennedy, and Bush convince an insecure and indecisive Lt. Buckland, now acting captain, that it would be appropriate to launch a surprise attack on the Spanish fortress at Santo Domingo. Matters are complicated when the inept Buckland incurs the enmity of the local rebels, who now regard them as enemies too. Captain Sawyer's increasing paranoia, deserting seamen, Buckland's growing jealousy of Hornblower, and the duplicity of the Spaniards all complicate the already perilous situation.

Hornblower leads a daring raid on a French sloop, and is rewarded by being allowed to set sail for England.

Finally promoted to Captain and given command of HMS Hotspur, Hornblower is sent to France to determine the status of Napoleon's pledge of peace, but instead he discovers Napoleon's troops waiting to invade. He also begins a romantic relationship with the young Maria Mason.

Promoted to Acting Lieutenant, Hornblower is forced to question his readiness for command.