crime genre research for my media film

Crime fiction is the genre of fiction that deals with crimes, their detection, criminals, and their motives. Most - though not all - crime novels crime novels share a common structure. First there is the crime, usually a murder; then there is the investigation; and finally the outcome or judgment, often in the shape of the criminal's arrest or death. Crime is usually distinguished from mainstream fiction and other genres such as science fiction or historical fiction, but boundaries can be, and indeed are, blurred. The genre's flexibility is perhaps one reason for its wide and enduring appeal and means different things to different people at different times. Unlike some literary fiction, the crime novel retains many of the time-honored techniques of fiction character, theme, narrative, tension, etc

There is now such a huge variety within the genre, it also has several sub-genres, including detective fiction (including the classic whodunnit), legal thriller, courtroom drama, hard-boiled fiction, Police Procedurals, Private Eye, Suspense, Thrillers and any other sub-genre in which a committed crime is the leading motivator of the plot. Indeed there are novels where the hero is the criminal not the detective.

All one can with any certainty is that the label "crime fiction" is a resilient convenience for those who use it, not an exact term.
The evolution of the print mass media in Britain and America in the latter half of the 19th century was crucial in popularizing crime fiction and related genres.