To Have and Have Not is a 1937 novel by Ernest Hemingway about Harry Morgan, a fishing boat captain who runs contraband and guns between Cuba and Florida. Legend has it that Hemingway wrote the book as part of a contractual obligation and hated it.

The 1944 film version, directed by Howard Hawks, moved the story's setting from Key West to Martinique under the Vichy regime.

In many ways the film is reminiscent of Michael Curtiz's Casablanca.

Harry "Steve" Morgan, played by Humphrey Bogart, ends up working for the French Resistance and falls for a pickpocket, "Slim," played by Lauren Bacall. It was her first film, at the age of 20. The film is remembered for the onscreen chemistry between Bogart and Bacall, most notably when Bacall asks Bogart "You know how to whistle, don't you?" The chemistry continued offscreen, causing Bogart's divorce and subsequent marriage to Bacall. They played opposite one another in a number of later films. In the movie, Bacall sings the song, "How Little We Know" by Hoagy Carmichael and Johnny Mercer. Hoagy plays the part in the film of the piano player, Cricket, who is actually composing that song. He also wrote the two other songs in the movie.

The second film version, titled The Breaking Point (1950), was directed by Michael Curtiz and starred John Garfield. It shifted the action to southern California and made Garfield a former PT Boat captain.