Raymond Chandler claimed that Martha Vickers gave such an intense performance as Carmen Sternwood that she completely overshadowed Lauren Bacall, and that much of Vickers' performance ended up on the cutting room floor as a result.
Due to Humphrey Bogart's affair with co-star Lauren Bacall, his marital problems escalated during filming, and his drinking often resulted in his being unable to work. Three months after the film was finished, Bacall and Bogart were married.
The scene where Humphrey Bogart and Lauren Bacall make suggestive talk about horses was added almost a year after filming was otherwise complete, in an attempt to inject the film with the kind of risqué innuendos that had made To Have and Have Not (1944), and Bacall, so popular a few years earlier.
William Faulkner came out to Hollywood to work on this film, but found that being around the set didn't agree with him, so he asked Howard Hawks if he could work "from home." Hawks agreed, assuming that Faulkner meant from his Hollywood apartment. Instead, Faulkner returned to his home in Oxford, Mississippi, leaving Hawks rather unhappy.
Many of the cars in the film have a "B" sticker in the lower-right corner of their 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 8 gallons of gas a week. Marlowe seems to use more than one week's allotment during a 72-hour period, which may be intended to reflect a black market in ration books. However, since Marlowe still has a deputy badge, at least in a deleted scene which existed in the 1945 version, he would be entitled to an X sticker (unlimited gas) as a peace officer. Perhaps the B sticker on the windshield was camouflage, since an X sticker would make the car extremely noteworthy. Marlowe also refers to "three red points," and speaks of a dead body as "cold meat" which refers to the red tokens used to acquire a family's allotment of meat during WWII.
The fussy persona that Marlowe adopts upon arriving in Geiger's bookstore has been a subject of argument for years; Lauren Bacall said that Humphrey Bogart came up with it while Howard Hawks claimed in interviews that it was his idea. What both of them failed to notice is that it was in the original book ("I had my horn-rimmed glasses on. I put my voice high and let a bird twitter in it."); all Bogart did was elaborate on it.
The film was completed on January 12, 1945 and was shown to American servicemen overseas, but was not released in the United States at that time. With the end of World War II, Warners pushed back the release of The Big Sleep (1946) in favor of its completed war-themed films, among these films was Confidential Agent (1945), which also starred Lauren Bacall. After her performance in that film was panned by the critics, agent Charles K. Feldman convinced Jack L. Warner that another failure would ruin Bacall's career. In a letter dated November 16, 1945, Feldman wrote Warner that "...if [Bacall] receives the same type of general reviews and criticisms on The Big Sleep, which she definitely will receive unless changes are made, you might lose one of your most important assets. Though the additional scenes will only cost in the neighborhood of probably $25,000 or $50,000, in my opinion this should be done even if the cost should run to $250,000." Feldman advised Warner to "give the girl at least three or four additional scenes with Bogart of the insolent and provocative nature that she had in To Have and Have Not (1944)."
Final film of Charles Waldron (Gen. Sternwood). He died before the film premiered. However, he appeared in three other 1946 releases that, despite opening earlier in the year than "The Big Sleep," were shot after it. James Stewart recreated the role in the 1978 remake in one of his last roles. Coincidentally, Waldron had played Stewart's father in Navy Blue and Gold (1937).
This was the film that began the long relationship between Howard Hawks and writer Leigh Brackett until his death in 1977. Hawks hired her after reading a story that she wrote entitled "No Good for a Corpse". However, when she was hired, she only finished half of another story that she wrote titled "Lorelei of the Red Mist". Her friend Ray Bradbury finished the last half.
When Marlowe is staking out Brody's apartment building prior to Mrs. Rutledge's arrival there are two inspection/ration stickers on the right wind shield of his car. Elsewhere in the film there are three.
The trivia items below may give away important plot points.
While working on the script, writers William Faulkner and Leigh Brackett couldn't figure out from the novel who murdered a particular character. So they phoned Raymond Chandler, who angrily told them the answer was right there in the book. They shrugged and returned to their work. Chandler soon phoned to say that he looked at the book himself and couldn't figure out who killed the character, so he left it up to them to decide. In the original cut, shown to the armed services, this question is resolved; in the film as released, it isn't.