The second book Patrick O'Brian wrote about the sea and a brilliant sequel to The Golden Ocean.

As in The Golden Ocean, The Unknown Shore tells the tale of another ill-fated ship on Anson's expedition round the world - the Wager. Parted from her squadron in the fearful storms off Cape Horn, the Wager struggles on alone up the ironbound coast of Chile, before she is driven onto rocks and sinks. The survivors include Jack Byron, a midshipman, and his eccentric protégé Toby, an alarmingly naive surgeon's mate with a single-minded devotion to zoology.

Faced with a surplus of rum, a disappearing stock of food, and a hard, detested captain, the survivors soon descend into trouble of every kind, including drunkeness, mutiny and bloodshed. As they make their way northwards under the guidance of a band of stony and depraved Indians, they at last find safety and good treatment in Valparaiso.

Admirers of O'Brian's Aubrey-Maturin novels will see in Jack Byron a matter-of-fact, bluff precursor to the great Jack Aubrey. Whilst Toby, raging in Greek against a corrupt Member of Parliament, stripped by thieves in the Farthing Pie House, asking the Commodore to carry his snake, arousing the darkest suspicions in the Chilean Inquisition, is an amiable companion whose vagaries afford endless diversion on a hard and dramatic journey.