Shortly after the events of
Post Captain, the Admiralty debates the prize money to be awarded to Aubrey and the other captains of the convoy involved in the
recent action off the coast of Portugal, in which several Spanish treasure ships were intercepted carrying the price of Spain's entry into the war on the side of France. On the quibble that Spain had not yet formally entered the war, the new
First Lord of the Admiralty decides the vast sum is a "
Droit of the Admiralty" and thus is not to be shared out with the captors. Jack is disheartened to hear that his reward will be much less than he and Sophia had expected. The First Lord also makes a blunder by mentioning the name of intelligence agent Stephen Maturin during the proceedings, putting Maturin at risk. Unconcerned, Stephen goes on a mission to Minorca and arranges for Jack, still acting commander of HMS
Lively and now on blockade duty near
Toulon, to pick him up at Port Mahon.
Lively pursues and burns a French supply ship, from which Jack gains valuable loot: a gunboat and a French signal book. When Stephen fails to show up at the rendezvous point, Jack learns from a Catalan revolutionary that his friend has been captured by French intelligence and is being held in Port Mahon in the former home of Admiral Harte, which Jack knows well. Jack and a rescue party use the captured gunboat and the French signals to slip into port unmolested. They storm the house and rescue Stephen, who has been brutally tortured, and kill most of the French interrogators. Back in England, Stephen tries to recover his strength and the use of his flayed hands. Jack is taken by bailiffs and held in a
sponging-house until he can pay off his debts. His marriage to Sophia Williams is deferred, as her mother insists that he be debt-free. Sir Joseph Blaine visits Stephen, who tells Blaine of his capture and Aubrey's predicament, requesting that Jack be advanced his pending reward and released. Blaine promises to help, and also gives Aubrey command of a new ship,
HMS Surprise. Before he embarks, Jack meets Sophia in a coach in the middle of the night, and they promise to marry no one else. Aubrey and Maturin depart in the
Surprise with orders to ferry an ambassador, Mr Stanhope, to the Sultan of Kampong on the
Malay Peninsula. Stanhope almost immediately takes to his cabin with seasickness.
Surprise is caught in the
doldrums north of the equator, and the crew begins to show signs of
scurvy. Stephen insists that they touch on the coast of Brazil to obtain fresh fruits. On a very hot Sunday, the doctor requests a boat for a quick visit to
St. Paul's Rock, and Second Lieutenant Nicolls agrees to row him out. The rocky islet and the nearby
Surprise are suddenly struck by intense squalls; Nicolls drowns and Stephen survives for two days on bird-fouled water and the blood of the resident
boobies. A badly damaged
Surprise recovers Stephen, who remarks that the days under the hot sun have restored his health after the torture. The ship then stops in Brazil for repairs. This is Stephen's first time in the
New World, so he explores the jungle and returns with a
sloth, which Jack introduces to alcohol. They also put in at
Rio for mail, where Jack learns that
Admiral Linois, who once took him prisoner, is patrolling the Indian Ocean at the head of a French squadron. Refitted and repainted,
Surprise maintains a cautious distance while rounding the
Cape of Good Hope, held by the Dutch who are allied with Napoleon. Nearing the waters of the
Antarctic Ocean,
Surprise endures a severe storm, and Stanhope becomes very ill. They put into
Bombay in
British India to refit after the storms and rest the ambassador. Stephen meets a local street child, a girl named Dil, who eagerly shows him around the city. He is watching a parade with Dil when he sees Diana Villiers, who has returned to Bombay ahead of her companion, the wealthy merchant Richard Canning. Stephen and Diana agree to visit, and spend several days together, at the end of which Stephen asks her to marry him. Diana does not give an answer but promises she will when
Surprise stops in
Calcutta. Stephen later finds Dil dead and her body looted of the valuables he had given her; he supervises her cremation on the shore. Soon after the voyage resumes Stanhope becomes ill again. His condition grows more serious with each passing day, and before reaching the
Sunda Strait they are compelled to find solid ground to help him recover. Pullings recommends a tiny beach surrounded by jungle, and they hastily bring the ambassador to it, where he dies a few hours later. Their mission now void,
Surprise sets sail for home. They encounter the
East India Company's China Fleet, returning to England unescorted. A day after departing the fleet,
Surprise spots Linois's squadron in the Indian Ocean.
Surprise engages its smallest ship, the corvette
Berceau, shredding her rigging; Jack bluffs by signaling to imaginary reinforcements beyond the horizon.
Surprise pretends to be badly damaged while speeding back to the China Fleet to warn them and organise a defence. Though some of the merchant captains want to flee before Linois arrives, Jack convinces them that the only way out of the situation is to fight. The largest ships of the China Fleet are disguised as
men-of-war and Jack distributes some of his officers to help them during the battle. As the French squadron closes on the
Indiamen,
Surprise engages Linois's warship, the
Marengo; she is outgunned and in peril when one of the Indiamen suddenly engages the French ship from the other side, forcing
Marengo to disengage. Damage forces Linois to abandon the chase in order to refit. Ashore in Calcutta, Aubrey receives an enthusiastic welcome from the merchants, including Canning, who are happy to pay for
Surprise repairs. As a personal reward, Canning offers Jack the opportunity to transport a chest of jewels as freight, which will earn him a portion of the cargo's value upon his arrival in England. Knowing the money will be enough to clear the last of his debts so he can marry Sophia, he immediately writes to her, asking her to meet him in
Madeira. During the refit, Stephen asks Diana for her answer to his marriage proposal, but Canning suddenly appears. In a fit of jealousy he slaps Stephen, who responds by challenging him to a duel. Canning's shot hits Stephen in the ribs, but Stephen's hits Canning in the heart, killing him. Stephen convinces Diana to return to England on a merchant ship that will leave immediately rather than tend to him as he recovers aboard the
Surprise. With the help of Aubrey, M'Alister, and a mirror, Stephen stoically operates on himself, removing the bullet lodged beneath his rib. Jack tends to his friend during the worst of his fever. In his delirium the usually private Stephen voices many of his thoughts and secrets. Arriving at Madeira, Jack is dismayed to learn that Sophia is not there; Stephen finds a note from Diana returning the ring he gave her and explaining that she has travelled to America with a wealthy man named Johnstone, whom she has agreed to marry. Stephen is devastated. Within a day's sailing, Jack overtakes the frigate HMS
Ethalion under his loyal friend Heneage Dundas and finds that Sophia is aboard. Jack wants to get married immediately, but Sophia insists they do it properly, when they return to England. ==Characters==