Humphrey Bogart plays Harry Morgan, owner-operator of charter boat in wartime Martinique. Morgan's right-hand man is Eddie (Walter Brennan), a garrulous alky whose pet question to anyone and everyone is Ever get stung by a dead bee?
While in port, Harry is approached by Free French activist Gerard (Marcel Dalio), who wants to charter Harry's boat to smuggle in an important underground leader. Adopting his usual I-stick-my-neck-out-for-no-one stance, Morgan refuses. Later on, he starts up a dalliance with Marie Browning (screen newcomer Lauren Bacall), an attractive pickpocket.
In order to help Marie return to America, Harry agrees to Gerard's smuggling terms. He uses his boat to bring resistance fighter De Bursac (Walter Molnar) and De Bursac's wife Helene (Dolores Moran) into Martinique. The Vichy police, suspecting that something's amiss, hold Morgan's pal Eddie hostage, tormenting the poor rummy by denying him liquor.
Predictably, Morgan comes to Eddie's rescue and manages to escape Martinique, with the delectable Marie as cozy company.
In the hands of director Howard Hawks and screenwriters Jules Furthman and William Faulkner, the end result bore only a passing relation to the original story by Ernest Hemingway: instead, it was a virtual rehash (but a good one!) of the recently released Casablanca, replete with several of that film's cast members.
The film's enduring popularity is primarily -- if not solely -- due to the sexy chemistry between Bogart and Bacall, especially in the legendary You know how to whistle, don't you? scene.
The most salutary result of To Have & Have Not was the subsequent Bogart-Bacall marriage, which endured until his death in 1957. It's widely believed that Lauren Bacall's singing voice was dubbed in by a pre-puberty Andy Williams; this is not true.
For the record, a more faithful-to-the-source cinemadaptation of the Hemingway original was filmed in 1950 as The Breaking Point.