Crime fiction is the literary genre that fictionalises crimes, their detection, criminals, action and their motives. It is usually distinguished from mainstream fiction and other genres such as historical fiction or science fiction, but the boundaries are indistinct. This is the basis of what crime thrillers are.
Crime thriller: This particular genre is a hybrid type of both crime films and thrillers that offers a suspenseful account of a successful or failed crime or crimes. These films often focus on the criminal(s) rather than a policeman. Central topics of these films include serial killers/murders, robberies, chases, shootouts, heists and double-crosses.

The crime thriller genre which includes movies such as The Girl on the Train, Momento, Memories of Murder and Vertigo came to life in the 1800's with the earliest known crime fiction being Thomas Skinner Sturr's anonymous Richmond, or Stories in the life of a Bow Street Officer back in 1827.
However this wasn't a full length crime fiction novel, the first full length crime fiction novel was Steen Steensen Blicher's The Reactor of Veilbye which was published in 1829. It is said the the Sherlock Holmes mysteries written by Arthur Conan Doyle have been singularly responsible fore the huge popularity in this genre.

The Crime Fiction has it's own subgenres, one being the Detective fiction subgenre with various forms of it being shown in a movie;
- The cozy mystery: a subgenre of detective fiction in which profanity, sex, and violence are downplayed or treated humorously.
- The locked room mystery: a specialised kind of a whodunit in which the crime is committed under apparently impossible circumstances, such as a locked room which no intruder could have entered or left.
- The whodunit: the most common form of detective fiction. It features a complex, plot-driven story in which the reader is provided with clues from which the identity of the perpetrator of the crime may be deduced before the solution is revealed at the end of the book.
- The Inverted detective story: Popularly called a "howcatchem," this is a genre of detective fiction where the reader is already aware of who the criminal is and the plot revolves around the detective discovering what the reader or audience already knows. The howcatchem was popularized by television shows such as Columbo and Barnaby Jones.
