Stephen Maturin is a main character in the Aubrey–Maturin series, which portrays his career as a physician, naturalist and spy in the Royal Navy during the Napoleonic Wars, and the long pursuit of his beloved Diana Villiers. As well as his activities as a physician and agent, Maturin is a celebrated naturalist (a member of the Royal Society) with a particular interest in birds, and the discoverer of the then unknown species of tortoise Testudo aubreii, which he named for Jack Aubrey. Maturin was played by Paul Bettany in the 2003 film adaptation Master and Commander: The Far Side of the World.