The bored navy lieutenant Jack Aubrey and physician/philosopher Stephen Maturin nearly
get in a duelat Port Mahon, Minorca. However, they become friends over their love of music after Aubrey is promoted to Commander of the brig Sophie. Maturin joins the crew as ship surgeon.
The Sophie accompanies a convoy of merchant ships and Aubrey connects with his sailors and discusses naval matters with Maturin.
After this assignment, the Sophie is allowed to sail independently on the hunt for French merchants. In a battle with the Spanish frigate Cacafuego the crew gains the respect of other officers except for Captain Harte who holds a grudge against Aubrey who ruins the possibility of tangible fame for Aubrey.
Later the Sophie is captured by French warships. Aubrey is court-martialed over the incident but is cleared of charges.