Jack Aubrey, Stephen Maturin and the rest of the company of the Diane are still stuck on the remote island in the East Indies, trying to build a craft from the remains of their ship. They are attacked by a group of warrior natives and just barely manage to beat them off, but at the cost of their half-built ship. A passing junk carries them back to Batavia, where the governorn, Raffles, gives them a small ship.

Jack plays a game of cat and mouse with a larger French frigate, but when they meet up with Tom Pullings in the Surprise, the Frenchman is defeated. Jack sails to Australia for refitting. On the way, the ship stops at a small island for repairs. They find two small native girls, all that remain of a population wiped out by smallpox. The sailors adopt them.

In Australia, Jack struggles with the tyrannical authorities while Stephen, with his friend Martin, explore the bush. Stephen is nearly killed by the sting of a platypus. He also finds out that his wife, Diana, has given birth to his daughter.