Just after the fight scene between Alan Ladd and the two thugs who kidnapped him, one of the thugs is seen soaking his broken leg in a round tub. That wasn't in the script; the actor had actually broken his leg filming the fight and, without consulting screenwriter Raymond Chandler, director George Marshall rewrote the script to have the character break his leg as well.

Elizabeth Short got the nickname "The Black Dahlia" from a bartender at a Long Beach bar she frequented. This film was playing at a theater down the street, and the bartender got the name wrong. Elizabeth picked up on that and kept the nickname, adding a flower to her hair to complete the transformation. She was murdered the next year (1947). The local newspapers dubbed the case the "Black Dahlia" as a morbid twist on this film's title. Unlike the movie, the Short murder case is still unsolved.

The pressure of having to finish the screenplay combined with the curve ball of having to write an entirely new ending was too much for Raymond Chandler. He quickly came down with a severe case of writer's block. According to a near-legendary story, screenwriter Raymond Chandler offered to finish the screenplay by working drunk: in exchange for sacrificing his health to produce the requisite pages on time, Chandler was permitted to work at home (a privilege rarely granted to screenwriters) and was provided two chauffeured cars, one to convey the completed pages to the studio and the other for his wife. Chandler turned the script in on time. Many now believe the "drunkenness" was simply a ruse by Chandler to wrangle extraordinary privileges from the desperate studio.

When the description of Morrison was given on the radio at the hotel the only thing missing was the suspect's height--possibly to avoid embarrassment to star Alan Ladd, who was only 5'6".

Many of the cars in the film have a "B" sticker on the windshields. This is a reflection of the wartime rationing of gasoline. Gas was rationed primarily to save rubber, because Japan had occupied Indochina, Malaysia and Indonesia (there was a shortage of gas on the East Coast until a pipeline from Texas was constructed to replace the transport of crude oil by sea). The B sticker was the second lowest category, entitling the holder to only eight gallons of gas a week.

The film was rushed into production in March, 1945, without a completed script, because Alan Ladd had been called up to return to military service. In 1943, Ladd had served in the U.S. Army for ten months, before being honorably discharged due to illness. However, he had recently been reclassified as 1-A (i.e. "fit for service"), and was due for re-induction in May 1945. This meant that Raymond Chandler was in a rush to finish the script, so the film could be completed in time. (In the end, all men aged 30 or over, including Ladd, would be released from the obligation.)

Raymond Chandler, who wrote the screenplay, claimed that producer John Houseman was in "the doghouse" and director George Marshall "was a stale old hack who had been directing for thirty years without once having achieved any real distinction", so Chandler went on to the Paramount set to direct some of the scenes himself.

This film was conceived primarily as a vehicle for Alan Ladd. Ladd was one of Paramount's brightest stars of the era but had been called back into service by the army. The situation sent the studio into a panic; it had no Ladd film ready for release and it was unclear when one of its most profitable stars would be able to work again. The studio assigned Ladd to this film and swiftly sped up production so it would have a movie featuring Ladd to release during his service time.

This was Raymond Chandler's first complete and original screenplay.

One of the reasons that Veronica Lake was selected to star opposite Alan Ladd was because of her height. Ladd was a notably short leading man (5' 6"), and Lake's similarly diminutive stature (4' 11") meant that the filmmakers did not have to make Ladd appear taller by comparison. At the same time, Ladd resented Doris Dowling, who played his wife in the film, because she was half a foot taller than him, and tried to have her replaced. The producers placated Ladd by having Dowling sitting or lying down during all her scenes with him.

Raymond Chandler was unhappy with Veronica Lake's performance as Joyce Harwood. He referred to the actress as "Miss Moronica Lake" and complained in a letter: "The only times she's good is when she keeps her mouth shut and looks mysterious. The moment she tries to behave as if she had a brain she falls flat on her face. The scenes we had to cut out because she loused them up! And there are three godawful close shots of her looking perturbed that make me want to throw my lunch over the fence."

Fourth pairing of Alan Ladd and Veronica Lake, although they only made cameo appearances in Star Spangled Rhythm (1942)

The Paramount brass told Raymond Chandler that if he didn't deliver the rest of the script ASAP the entire future of the studio would be in jeopardy. As an incentive, the studio offered him a $5,000 bonus to hurry up and finish the script. This backfired, however, as Chandler considered it a "bribe," an insult to his reputation, and a means of putting more pressure on him to finish a script where the logical ending had already been compromised by the studio.

Raymond Chandler almost walked off the film when George Marshall improvised dialogue. " . . . it is ludicrous to suggest that any writer in Hollywood, however obstreperous, has a 'free hand' with a script;" said Chandler, "He may have a free hand with the first draft, but after that they start moving in on him. Also what happens on the set is beyond the writer's control. In this case I threatened to walk off the picture, not yet finished, unless they stopped the director putting in fresh dialogue out of his own head."

Raymond Chandler insisted on writing the script from home. He relied on alcohol, as it helped him write. He also presented a list of requirements that he would need in order to fulfil his obligation. They included "two Cadillac limousines, to stand day and night outside the house with drivers available," "six secretaries," and "a direct line open at all times to my office by day, to the studio switchboard at night and to my home at all times."

One of over 700 Paramount productions, filmed between 1929 and 1949, which were sold to MCA/Universal in 1958 for television distribution, and have been owned and controlled by Universal ever since. Because of legal complications, it was not cleared for telecast in the USA until February 1962. It was released on DVD 10 June 2013 by Turner Classic Movies as part of the Universal Collection, and again 10 November 2014 as part of Universal's Film Noir Movie Spotlight Collection, and, since that time, has also enjoyed occasional cable TV presentations on Turner Classic Movies.

"The Screen Guild Theater" broadcast a 30-minute radio adaptation of the movie on April 21, 1949, with Veronica Lake and Alan Ladd reprising their film roles.

Will Wright / Dad Newell says his age is 57. This was his actual age. A veteran character actor, his was a very familiar face on popular TV shows of the fifties and early sixties.

When Johnny approaches the bungalow, the party goers are singing, Ac-Cent-Tchu-Ate the Positive. Written and performed by Johny Mercer in 1944, it was a popular song that looked forward to an end of WWII and which helped set the mood for post-war America. Decades later, this song was featured in the film L.A. Confidential (1997), in order to set the mood for the same period (1950).

Final film of Don Costello

Buzz tells Helen that he would bring Johnny home even if he had to "frog march" him. This is where one person grabs another from the back by the belt and the collar, lifts up on the belt to put pressure at the crotch, making him stand on his toes, then pushes him forward to make him walk in a manner resembling a frog.

Some sources erroneously include Harold J. Stone in an undetermined, uncredited minor role; Stone does not appear in this film in any capacity. At the time it was filmed (in Hollywood), he was in New York City appearing on the stage in a prominent role in "A Bell for Adano" (1944-45).

This was the first screenplay on which Chandler worked without a collaborator.

William Bendix' character has a steel plate in his head which causes headaches when he hears loud music.

Raymond Chandler was quite disappointed that the Naval War Office forced him to change the ending of the script in order to avoid disparaging an American serviceman. Chandler's original ending pegged Buzz as the killer, but largely absolved him of his actions due to his war injuries and the psychological impact that WWII had on him. A few weeks after the film's release, Chandler wrote "What the Navy Department did to the story was a little thing like making me change the murderer and hence make a routine whodunit out of a fairly original idea. What I wrote was a story of a man who killed (executed would be a better word) his pal's wife under the stress of a great and legitimate anger, then blanked out and forgot all about it; then with perfect honesty did his best to help the pal get out of a jam, then found himself in a set of circumstances which brought about partial recall. The poor guy remembered enough to make it clear who the murderer was to others, but never realized it himself. He just did and said things he couldn't have done or said unless he was the killer; but he never knew he did them or said them and never interpreted them."

The original denouement as written by Raymond Chandler had Buzz as the murderer. However, since the movie was released so close to the end of WWII, the Navy preferred that a returning veteran not be shown as the killer. Therefore the ending was re-written for a different killer.