The film was reviewed under it's pre-release title Uncle Harry. According to information contained in the file on the film in the MPPA/PCA Collection at the AMPAS Library, the Breen office first took an interest in Thomas Job's play in 1939, when it was submitted to them by British producer Herbert Wilcox, who was considering the material for an RKO production. On 31 Oct 1939, PCA director Joseph I. Breen stated in an internal memo that he would reject any filming of Job's play with its current ending. In the play, the character of "Uncle Harry" accidentally kills one sister, while the other, the one whom he was trying to murder, is executed for the crime. Harry, who is unable to convince anyone that he is the real murderer, receives his only punishment from his own conscience. On 3 Nov 1939, Breen notified RKO that he was officially rejecting the material, as it suffered from an "unsatisfactory treatment of the leading character, who is a murderer."
       In Feb 1943, HR news items stated that Republic Pictures had purchased the screen rights to Uncle Harry, with the intention of casting Paul Muni in the title role. On 18 Feb 1943, however, HR reported that Clifford Hayman, the producer of the New York stage production, denied the sale of the play to Republic. In May 1943, the Job play was once more submitted by RKO to the Breen office, this time as a possible project for German director Fritz Lang. In this submission, however, Harry's character had been institutionalized in a mental hospital and the story unfolded within that framework. With some reservations, Breen notified RKO on 27 May 1943 that this change might make Uncle Harry acceptable film material. Later, in Oct 1943, Twentieth Century-Fox contacted the Hays office about producing its own adaptation of Uncle Harry, and, like RKO, was told by Breen that the play, as originally written, was not acceptable.
       According to information found in the Charles K. Feldman papers at the AFI Louis B. Mayer Library, Universal purchased the screen rights to the play on 23 Nov 1943. LAEx news items listed the purchase price at $100,000. Agent and producer Charles K. Feldman then purchased the rights to Uncle Harry from Universal for $50,000 on 3 Dec 1943. Under that agreement, Universal would produce and distribute the film in association with Feldman, and the purchase price was to be taken from Universal's future payments to Feldman for his share of the profits from two 1942 Universal releases, Pittsburgh and The Spoilers, and his current production of Three Cheers for the Boy, which was released by Universal in 1944 as Follow the Boys (see entries above and below). On 14 Apr 1944, Feldman then sold Uncle Harry back to Universal for $150,000, plus twenty-five-per-cent of the film's net profits in excess of the first $200,000. This agreement faced some legal hurdles, however, as producer Charles R, Rogers claimed that his company had an oral agreement with Feldman to produce Uncle Harry. It has not been determined how Feldman and Rogers settled their dispute.
       According to the Feldman papers, the first treatment for the Universal production of Uncle Harry was finished on 14 Sep 1944, authored by screenwriter Keith Winters and producer Joan Harrison. Winters then completed the first draft of the screenplay on 20 Mar 1944. Writer Stephen Longstreet was later brought onto the project and his final draft of The Strange Affair of Uncle Harry was turned in on 6 Mar 1945. Longstreet received sole writing credit for the screenplay; Winters is credited with the play's adaptation. According to the MPPA/PCA records, Universal's production of The Strange Affair of Uncle Harry met with little resistance from the Breen Office.
       On 19 Aug 1945, NYT reported that Universal had been previewing the film with five different endings, over a ten-day period, at an unnamed Los Angeles theater. NYT then reported on 26 Aug 1945 that Universal had decided to use the ending given in the above summary, in which the murder of Hester is only a dream. According to the MPPA/PCA files, the approved storyline for The Strange Affair of Uncle Harry was similar to the plot submitted by RKO in May 1943, with Harry telling his story to "Dr. Adams" and "Deborah Brown," his ex-fiancée, as he prepares to board a train that will take him to a mental institution. It has not been determined if that ending was one of the four shot, then rejected, by the studio. According to Life magazine, producer Harrison ended her association with Universal over her disagreement with the studio's editorial decision.
       Studio financial reports found in the Feldman papers state that The Strange Affair of Uncle Harry had a negative cost of $886,100, and that, by Nov 1957, it had grossed $945,400 domestically, with a world-wide box office of $1,541,000. On 2 Nov 1957, Universal sold the film for $100,000 to the National Telefilm Assoc., which re-released it under the title Zero Murder Case. According to the Feldman Papers, the film had previously been re-released by Realart Pictures, Inc. in 1947. HR news items include Louis Jean Heydt in the cast, but his appearance in the released film has not been confirmed.