Being a low-budget horror film with multiple stories, an international cast and foreign financial backing, "Black Sabbath" follows numerous trends of 1960s Italian film productions. The film is credited to various writers, including Anton Chekov and Aleski Tolstoy, but is predominantly based on several uncredited sources, and changes were made to the script after filming commenced. American International Pictures and Titra Sound Corporation suggested changes to Bava during filming to make the film palatable for American audiences, and created their own English-language version of the film, which replaced Roberto Nicolosi's score with music by Les Baxter, removed several depictions of graphic violence and made alterations to other scenes. This version greatly changed the plot of "The Telephone", giving it a supernatural element and removing all references to lesbianism and prostitution.