Over a blank screen, offscreen narrator Bert Holland opens the film with the now famous words: “Ladies and gentlemen, the story you are about to see is true. The names have been changed to protect the innocent.” (On the Dragnet television show, this introduction was given by announcer George Fenneman.) The scene of Starkie’s killing then precedes the opening titles. The credits above the title read: “Warner Bros. presents Jack Webb as Sergeant Joe Friday in the Screen Play by Richard L. Breen.” Voice-over narration by Webb continues intermittently throughout the film, providing clarification and exact dates and times for each event, as in a police report.
       The combination of drama and semi-documentary style used in the film version of Dragnet was already familiar to audiences of 1954, as that had been the format of the popular radio and television series of the same name. Both were developed by Webb. Before Dragnet, Webb had been a radio actor (see note for Danger Ahead) and appeared as a forensics expert in a documentary-style police drama, the 1948 Eagle-Lion Films production of He Walked by Night, directed by Alfred Werker (see AFI Catalog of Feature Films, 1941-50.) Webb then developed and starred in the Dragnet radio show, which began in 1949, and which was similar in style to He Walked by Night. After a special preview of Dragnet was telecast on the Chesterfield Sound Off Time program in Dec 1951, the television shows aired intermittently on the NBC network from 3 Jan 1952 through Sep 1959.
       A Jan 1954 LAT news item, written around the time that the one hundredth episode of the television show had been completed, announced that a Dragnet film, which would be produced in color by Jack L. Warner, director Webb and Stanley Meyer of Mark VII, Ltd., would start production within ninety days. According to the news item, Mark VII, which produced the television series, had already produced the first major color production to appear on television networks, The Dragnet Christmas Story. Modern sources state that Warner Bros. paid Webb $800,000 to make the film version and gave him complete creative control.
       Like its radio and television predecessors, the film was based on an actual Los Angeles police case and maintained the same format, progressing in a linear fashion through “Joe Friday’s” workday. The MPH review described the film as a “documentary recital of every-day police work.” Friday’s characteristic terse comments, which were described in the NYT review as his “fetish for conciseness,” and the abrupt musical stingers that often punctuated them in the television series, were retained in the film version. Many of the actors who appeared in the television episodes were also featured in the film. However, as Webb explained in an Apr 1954 LAT article, the film broke with its own tradition by identifying the killers for the audience before the police solved the case. There is more graphic violence in the film than in the broadcast versions, as the particular story chosen for the film was too violent to be shown on television. The MPH review notes that the film, in particular the murder scene and the fistfight at the poker game, “equals or surpasses others of its kind in the modern trend toward detailed brutality.”
       The characteristic prologue stating a final accounting of justice for each character is missing in the film version. The famous four-note musical signature [“dum-de-dum-dum”], which a modern source described as “possibly the most famous four-note introduction since Beethoven’s Fifth Symphony," was usually heard at the beginning of each television story, but was saved for the end of the film. The theme was inspired by a phrase from Miklos Rozsa's "Danger Ahead" theme, which appears in the 1946 Universal production, The Killers (see AFI Catalog of Feature Films, 1941-50). Although Rozsa is not credited for his contribution to the Dragnet film, he is given onscreen credit in a later incarnation of Dragnet, a 2003 television series.
       According to a Sep 1954 HR article, the vacant lot used in the first scene was rented by Webb in early spring, so that flower seeds could be sown and bloom in time for May production. One sequence in the film was shot at the Los Angeles County Museum of Natural History. Although their appearance has not been confirmed, May and Jul 1943 HR news items add the following performers to the cast: D. H. Depatie, E. Hollingsworth, Harold Fisher, Stanley Martin, Bert Stevens, and the Herm Saunders Trio. The Pete Kelly’s Blues Radio Orchestra, the jazz combo featured in the film, also appeared in the 1955 Warner Bros. production, Pete Kelly's Blues, which was produced and directed by Webb (for additional information, see entry). Eddie King, who plays himself in Dragnet, was an NBC staff announcer.
       After the original television series, which, like the film, also co-starred Ben Alexander, a revival series, Dragnet ‘67, ran from Jan 1967 through Sep 1970, again starring Webb, but co-starring Harry Morgan as his partner. Webb died in 1982, but another Dragnet series aired during the 1989-90 television season, starring Jeff Osterhage and Bernard White. However, the new version was overshadowed by the popularity of the new kind of realism in other police shows, such as Cops and America’s Most Wanted, and was short-lived. In Feb 2003, a new Dragnet series debuted on the ABC television network, starring Ed O'Neill and Ethan Embry. The series was written and produced by Dick Wolf. In a subplot of the 1997 Warner Bros. police drama, L. A. Confidential, actor Kevin Spacey's character, who is a Los Angeles policeman during the 1950s, serves as technical advisor for a television show that is intentionally reminiscent of Dragnet. The catchphrase, "just the facts," is spoken several times in the film.
       Dragnet’s distinctive style has inspired many parodies in skits, film, jokes, and everyday life, including the 1953 hit comedy record by Stan Freberg, "St. George and the Dragonet." The idiosyncracies of the Dragnet opus—the four-note musical theme, the musical stingers to emphasize a character's line, Friday’s catchphrases, the staccato dialogue police jargon and dramatic irony—continue to be part of vernacular humor.