If Faulkner had his way, The Big Sleep would have an entirely different ending with the Philip Marlowe character, played by Bogart, tricking the murderer into taking a bullet intended for the private detective. However, the film censors rejected Faulkner and co-author Leigh Brackett's version because the Production Code would not permit the leading man to "take the law into his own hands." The studio used an alternate ending, written by author Jules Furthman, where the villain enters a mental institution.

Faulkner's script-writing career began to slow down in the late 1940s and early 1950s. Increasingly, what little screenwriting he attempted was ignored. The studio, for instance, completely abandoned Faulkner's screenplay for the adaptation of Stephen Longstreet's novel Stallion Road (1945). The book's author had to complete the task for the 1947 film starring future U.S. president Ronald Regan. Faulkner's version remained unpublished until 1989 when it was released by the University Press of Mississippi.

The last two scripts Faulkner wrote for Hawks were The Left Hand of God (1955) and Land of the Pharaohs (1955). Hawks dumped Faulkner's screenplay of The Left Hand of God due to warnings from a Catholic priest that the risqué subject matter would startle moviegoers. Land of the Pharaohs stars the young actress Joan Collins, as the evil Princess Nelliter. After this project Faulkner worked occasionally for television but never returned to film.