Other Subgenres
There is also a subgenre of historical detectives. See historical whodunnit for an overview.
The first amateur railway detective, Thorpe Hazell, was created by Victor Whitechurch and his stories impressed Ellery Queen and Dorothy L. Sayers.
"Cozy mysteries" began in the late 20th century as a reinvention of the Golden Age whodunnit; these novels generally shy away from violence and suspense and frequently feature female amateur detectives. Modern cozy mysteries are frequently, though not necessarily in either case, humorous and thematic (culinary mystery, animal mystery, quilting mystery, etc.)
Another subgenre of detective fiction is the serial killer mystery, which might be thought of as an outcropping of the police procedural. There are early mystery novels in which a police force attempts to contend with the type of criminal known in the 1920s as a homicidal maniac, such as a few of the early novels of Philip Macdonald and Ellery Queen's Cat of Many Tails. However, this sort of story became much more popular after the coining of the phrase "serial killer" in the 1970s and the publication of The Silence of the Lambs in 1988. These stories frequently show the activities of many members of a police force or government agency in their efforts to apprehend a killer who is selecting victims on some obscure basis. They are also often much more violent and suspenseful than other mysteries.
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