The Last One Left (1966) is a mystery novel by John D. MacDonald. The story largely takes place in southern Florida and the Bahamas, and is similar to many of the author's Travis McGee stories. The book is in fact dedicated to McGee "who lent invaluable support and encouragement," and a named runabout motorboat later appears in the McGee novel Pale Gray for Guilt. It was originally published in 1967, appearing in paperback by Fawcett (reprinted 1981) and in hardcover by Doubleday. From internal evidence (the Bay of Pigs Invasion is mentioned but the Bahamian dollar is not yet in circulation) the action occurs in late May and early June, circa 1965.

A yacht explodes in the Bahamas, apparently killing 6 people and leaving its burned captain temporarily marooned on a small island. Sam Boyleston, an attorney from Texas and the brother of one of the victims, investigates the circumstances, as does Raoul Kelly, a newspaper reporter. As the plot develops it becomes apparent that one person is ruthlessly manipulating events, but proving guilt appears impossible.

The book's subtitle is A story about money and dying, and it is written on several different levels. Throughout the plot are subtle discourses on what it means to have a "good" life, how people deal with stress and uncertainty, and at what point will someone reach out for healthy human contact, or else take self-interest as their highest goal.