The document analyzes how camera work, sound, editing, and mise-en-scène are used in the film Saw IV to convey messages about the plot, characters, and genre, and to create mysteries for the audience. Long shots of a dead body on an examination table introduce mysteries around who the man is and his relevance to the plot. Flashbacks and close-ups during the autopsy foreshadow the discovery of a hidden object and give the impression the man had a mysterious past. Cross-cutting between the body and sharp tools in the laboratory hints they are linked and establishes the setting. Frequent close-ups of gore and blood emphasize the horror genre.