The Mauritius Command: Aubrey-Maturin Series, Book 4 (Unabridged‪)‬

In The Mauritius Command, Captain Jack Aubrey is ashore on half-pay without a command until his friend, occasional intelligence agent Stephen Maturin, arrives with secret orders for Aubrey to take a frigate to the Cape of Good Hope under a Commodore's pennant. But the difficulties of carrying out his orders are compounded by two of his own captains: one a pleasure-seeking dilettante, the other liable to provoke the crew to mutiny.

Based on an actual campaign of 1810 in the Indian Ocean, O'Brien's attention to the detail of early 19th-century life ashore and at sea is meticulous. This tale is as beautifully written and as gripping as any in the series; it also stands on its own as a superlative work of fiction.