The history of the genre is, to a large extent, the history of the detective's character, detailed earlier in this essay. Early detective novels combined elements of the Gothic, that which could not be explained, with crime stories, both popularized in the eighteenth century. By the end of the nineteenth century, schema were in place for the writing of detective fiction, as an article by S. S. Van Dine published in 1929 entitled "Twenty Rules for Writing Detective Stories" attests. In 1930 Dorothy Sayers founded The Detection Club, which set up rules for "fair play" in detective fiction. Many of the characteristics of the early fiction are recognizable in O Is for Outlaw, such as the emphasis on observation and the powers of rationalism, identification of a criminal, and a solution based on information within the fiction.

The genre has always been popular with women writers, perhaps initially...