The Aubrey and Maturin series comprises twenty novels that chronicle the adventures of two particular friends, Jack Aubrey and Stephen Maturin. Master and Commander begins on April 1st, 1800 in Port Mahon, Minorca, at the time a British naval base. Aubrey is a captain (technically he is a lieutenant, with a position of Master and Commander) in the Royal Navy. Maturin is a half-Irish, half-Catalan physician, natural philosopher, and agent for British naval intelligence.
The novel introduces the two main characters and gives Jack his first ship, HMS Sophie. Jack and Stephen become acquainted, and Stephen accepts a position as Sophie's surgeon. We also meet Pullings and Mowett, who become permanent fixtures in the series, and James Dillon, Sophie's first lieutenant, whose secret past intersects Stephen's own.
It is largely based on The Far Side of the World, the tenth novel in the Aubrey/Maturin series. Among the changes in the adaptation is that the American frigate harassing British whaling interests in the book becomes a French privateer in the film.
The movie's success and the wide open ending has led to credible speculation about a sequel.