Armchair detective an arm-chair, my brother would be the greatest criminal agent that ever lived." "The first example of armchair detecting can be found in the work of Edgar Allan Poe. In "The Mystery of Marie Rogêt" (1842), C. Auguste Dupin, working wholly from newspaper accounts, arrives at the correct explanation for a young woman's mysterious disappearance." Baroness Orczy's Old Man in the Corner sits in a restaurant and talks to an acquaintance about cases, almost always finishing by revealing that he has solved the crime. A more literal use of this term can be found in Rex Stout's Nero Wolfe novels
Police procedural gathering evidence, search warrants, interrogation and adherence to legal restrictions and procedure. The roots of the police procedural have been traced to at least the mid-1880s. Wilkie Collins's novel "The Moonstone" (1868), a tale of a Scotland Yard detective investigating the theft of a valuable diamond, has been described as perhaps the earliest clear example of the genre. As detective fiction rose to worldwide popularity in the late 1800s and early 1900s, many of the pioneering and most popular characters, at least in the English-speaking world, were private investigators or amateurs. See C. Auguste Dupin, Sherlock Holmes, Sam Spade, Miss