Of these four kinds of literary entertainment the detective novel is the youngest, the most complicated, the most difficult of construction, and the most distinct. It is, in fact, almost sui generis, and, except in its more general structural characteristics, has little in common with its fellows — the romantic, the adventurous, and the mystery novel. In one sense, to be sure, it is a highly specialized offshoot of the last named; but the relationship is far more distant than the average reader imagines.
II
If we are to understand the unique place held in modern letters by the detective novel, we must first endeavor to determine its peculiar appeal: for this appeal is fundamentally unrelated to that of any other variety of fictional entertainment. What, then, constitutes the hold that the detective novel has on all classes of people — even those who would not stoop to read any other kind of “popular” fiction? Why do we find men of high cultural attainments — college professors, statesmen, scientists, philosophers, and men concerned with the graver, more advanced, more intellectual problems of life — passing by all other varieties of bestseller novels, and going to the detective story for diversion and relaxation?
The answer, I believe, is simply this: the detective novel does not fall under the head of fiction in the ordinary sense, but belongs rather in the category of riddles: it is, in fact, a complicated and extended puzzle cast in fictional form. Its widespread popularity and interest are due, at bottom and in essence, to the same factors that give popularity and interest to the cross-word puzzle. Indeed, the structure and mechanism of the cross-word puzzle and of the detective novel are very similar. In each there is a problem to be solved; and the solution depends wholly on mental processes — on analysis, on the fitting together of apparently unrelated parts, on a knowledge of the ingredients, and, in some measure, on guessing. Each is supplied with a series of overlapping clues to guide the solver; and these clues, when fitted into place, blaze the path for future progress. In each, when the final solution is achieved, all the details are found to be woven into a complete, interrelated, and closely knitted fabric.
There is confirmatory evidence of the mechanical impulse that inspires the true detective novel when we consider what might almost be called the dominant intellectual penchant of its inventor. Poe, the originator of the modern detective story, was obsessed with the idea of scientific experimentation. His faculty for analysis manifested itself in his reviews and in the technicalities of his poetry; it produced “Maelzel’s Chess-Player”; it led him into the speculative ramifications of handwriting idiosyncrasies in “A Chapter on Autography”; it brought forth his exposition of cryptograms and code-writing in “Cryptography”; and it gave birth to his acrostic verses. His four analytic stories — “The Murders in the Rue Morgue”, “The Mystery of Marie Rogêt”, “The Gold-Bug,” and “The Purloined Letter” — were but a literary development, or application, of the ideas and problems which always fascinated him. “The Gold-Bug,” in fact, was merely a fictional presentation of “Cryptography”. (Incidentally, the number of detective stories since Poe’s day that have hid their solutions in cipher messages is legion).
There is no more stimulating activity than that of the mind; and there is no more exciting adventure than that of the intellect. Mankind has always received keen enjoyment from the mental gymnastics required in solving a riddle; and puzzles have been its chief toy throughout the ages. But there is a great difference between waiting placidly for the solution of a problem, and the swift and exhilarating participation in the succeeding steps that lead to the solution. In the average light novel of romance, adventure, or mystery, the reader merely awaits the author’s unraveling of the tangled skein of events. True, during the waiting period he is given emotion, wonder, suspense, sentiment and description, with which to occupy himself; and the average novel depends in large measure on these addenda to furnish his enjoyment. But in the detective novel, as we shall see, these qualities are either subordinated to ineffectuality, or else eliminated entirely. The reader is immediately put to work, and kept busy in every chapter, at the task of solving the book’s mystery. He shares in the unfoldment of the problem in precisely the same way he participates in the solution of any riddle to which he applies himself.
Because of this singularity of appeal the detective novel has gone its own way irrespective of the progressus of all other fictional types. It has set its own standards, drawn up its own rules, adhered to its own heritages, advanced along its own narrow-gage track, and created its own ingredients as well as its own form and technic. And all these considerations have had to do with its own isolated purpose, with its own special destiny. In the process of this evolution it has withdrawn farther and farther from its literary fellows, until to-day it has practically reversed the principles on which the ordinary popular novel is based.
A sense of reality is essential to the detective novel. The few attempts that have been made to lift the detective-story plot out of its naturalistic environment and confer on it an air of fancifulness have been failures. A castles-in-Spain atmosphere, wherein the reader may escape from the materiality of every day, often gives the average popular novel its charm and readability; but the objective of a detective novel — the mental reward attending its solution — would be lost unless a sense of verisimilitude were consistently maintained, — a feeling of triviality would attach to its problem, and the reader would experience a sense of wasted effort. This is why in cross-word puzzles the words are all genuine: their correct determination achieves a certain educational, or at least serious, result. The “trick” cross-word puzzle with coined words and purely logomachic inventions (such as filling four boxes with e’s — e-e-e-e — for the word “ease”, or with i’s — i-i-i-i — for the word “eyes”, or making u-u-u-u stand for the word “use”) has never been popular. The philologic realism, so to speak, is dissipated. A.E.W. Mason has said somewhere that Defoe would have written the perfect detective story. He was referring to Defoe’s surpassing ability to create a realistic environment.
This rule of realism suggests the common literary practice of endowing mises en scéne with varying emotional pressures. And here again the detective novel differs from its fictional confreres; for, aside from the primary achievement of a sense of reality atmospheres, in the descriptive and psychic sense, have no place in this type of story. Once the reader has accepted the pseudo-actuality of the plot, his energies are directed (like those of the detective himself) to the working out of the puzzle; and his mood, being an intellectual one, is only distracted by atmospheric invasions. Atmospheres belong to the romantic and the adventurous tale, such as Poe’s “The Fall of the House of Usher” and Scott’s Ivanhoe, and to the novel of mystery — Henry James’s The Turn of the Screw and Bram Stoker’s Dracula, for instance.
The setting of a detective story, however, is of cardinal importance. The plot must appear to be an actual record of events springing from the terrain of its operations; and the plans and diagrams so often encountered in detective stories aid considerably in the achievement of this effect. A familiarity with the terrain and a belief in its existence are what give the reader his feeling of ease and freedom in manipulating the factors of the plot to his own (which are also the author’s) ends. Hampered by strange conditions and modes of action, his personal participation in the story’s solution becomes restricted and his interest in its sequiturs wanes. A detective novel is nearly always more popular in the country in which it is laid than in a foreign country where the conditions, both human and topographic, are unfamiliar. The variations between English and American customs and police methods, and mental and temperamental attributes, are, of course, not nearly so marked as between those of America and France; and no sharp distinction is now drawn between the English and the American detective tale. But many of the best French novels of this type have had indifferent sales in the United States. Gaston Leroux’s The Mystery of the Yellow Room, The Perfume of the Lady in Black, and The Secret of the Night have never had their deserved popularity in this country because of their foreign locales; but The Phantom of the Opera, by the same author, which is a sheer mystery story, has been a great success here, due largely to that very unfamiliarity of setting that has worked against the success of his detective novels.
III
In the matter of character-drawing the detective novel also stands outside the rules governing ordinary fiction. Characters in detective stories may not be too neutral and colorless, nor yet too fully and intimately delineated. They should merely fulfil the requirements of plausibility, so that their actions will not appear to spring entirely from the author’s preconceived scheme. Any closely drawn character analysis, any undue lingering over details of temperament, will act only as a clog in the narrative machinery. The automaton of the cheap detective thriller detracts from the reader’s eagerness to rectify the confusion of the plot; and the subtly limned personality of the “literary” detective novel shunts the analytic operations of the reader’s mind to extraneous considerations. Think back over all the good detective stories you may have read, and try to recall a single memorable personality (aside from the detective himself). And yet these characters were of sufficient color and rotundity to enlist your sympathetic emotions at the time, and to drive you on to a solution of their problems.
The style of a detective story must be direct, simple, smooth, and unencumbered. A “literary” style, replete with descriptive passages, metaphors, and word pictures, which might give viability and beauty to a novel of romance or adventure, would, in a detective yarn, produce sluggishness in the actional current by diverting the reader’s mind from the mere record of facts (which is what he is concerned with), and focussing it on irrelevant aesthetic appeals. I do not mean that the style of the detective novel must be bald and legalistic, or cast in the stark language of commercia1 documentary exposition; but it must, like the style of Defoe, subjugate itself to the function of producing unadorned verisimilitude. No more is gained by stylizing a detective novel than by printing a cross-word puzzle in Garamond Italic, or Cloister Cursive, or the Swash characters of Caslon Old-style.
The material for the plot of a detective novel must be commonplace. Indeed, there are a dozen adequate plots for this kind of story on the front page of almost any metropolitan daily paper. Unusualness, bizarrerie, fantasy, or strangeness in subject-matter is rarely desirable; and herein we find another striking reversal of the general rules applying to popular fiction; for originality and eccentricity of plot may give a novel of adventure or mystery its main interest. The task confronting the writer of detective fiction is again the same confronting the cross-word-puzzle manufacturer — namely, the working of familiar materials into a difficult riddle. The skill of a detective story’s craftsmanship is revealed in the way these materials are fitted together, the subtlety with which the clues are presented, and the legitimate manner in which the final solution is withheld.
Furthermore, there is a strict ethical course of conduct imposed upon the author. He must never once deliberately fool the reader: he must succeed by ingenuity alone. The habit of inferior writers of bringing forward false clues whose purpose is to mislead is as much a form of cheating as if the cross-word-puzzle maker should print false definitions to his words. The truth must at all times be in the printed word, so that if the reader should go back over the book he would find that the solution had been there all the time if he had had sufficient shrewdness to grasp it. There was a time when all manner of tricks, deceits, and far-fetched devices were employed for the reader’s befuddlement; but as the detective novel developed and the demand for straightforward puzzle stories increased, all such methods were abrogated, and to-day we find them only in the cheapest and most inconsequential examples of this type of fiction.
In the central character of the detective novel — the detective himself — we have, perhaps, the most important and original element of the criminal-problem story. It is difficult to describe his exact literary status, for he has no counterpart in any other fictional genre. He is, at one and the same time, the outstanding personality of the story (though he is concerned in it only in an ex-parte capacity), the projection of the author, the embodiment of the reader, the deus ex machina of the plot, the propounder ot the problem, the supplier of the clues, and the eventual solver of the mystery. The life of the book takes place in him, yet the life of the narrative has its being outside of him. In a lesser sense, he is the Greek chorus of the drama. All good detective novels have had for their protagonist a character of attractiveness and interest, of high and fascinating attainments — a man at once human and unusual, colorful and gifted. The buffoon, the bungler, the prig, the automaton — all such have failed. And sometimes in an endeavor to be original an otherwise competent writer, misjudging the psychology of the situation, has presented us with a farcical detective or a juvenile investigator, only to wonder, later on, why these innovations failed. The more successful detective stories have invariably given us such personalities as C. Auguste Dupin, Monsieur Lecoq, Sherlock Holmes, Dr. Thorndyke, Rouletabille, Dr. Fortune, Furneaux, Father Brown, Uncle Abner, Richard Hannay, Arsène Lupin, Dawson, Martin Hewitt, Max Carrados and Hanaud — to name but a few that come readily to mind. All the books in which these characters appear do not fall unqualifiedly into the true detective-story category; but in each tale there are sufficient elements to permit broadly of the detective classification. Furthermore, these Oedipuses themselves are not, in every instance, authentic sleuths: some are doctors of medicine, some professors of astronomy, some soldiers, some journalists, some lawyers, and some reformed crooks. But their vocations do not matter, for in this style of book the designation “detective” is used generically.
We come now to what is perhaps the outstanding characteristic of the detective novel: its unity of mood. To be sure, this is a desideratum of all fiction; but the various moods of the ordinary novel — such as love, romance, adventure, wonder, mystery — are so closely related that they may be intermingled or alternated without breaking the thread of interest; whereas, in the detective novel, the chief interest being that of mental analysis and the overcoming of difficulties, any interpolation of purely emotional moods produces the effect of irrelevancy — unless, of course, they are integers of the equation and are subordinated to the main theme. For instance, in none of the best detective novels will you find a love interest, — Sherlock Holmes in mellow mood, holding a lady’s hand and murmuring amorous platitudes, would be unthinkable. And when a detective is sent scurrying on a long-drawn-out adventure beset with physical dangers, the reader fumes and frets until his hero is again in his armchair analyzing clues and inquiring into motives.
In this connection it is significant that the cinematograph has never been able to project a detective story. The detective story, in fact, is the only type of fiction that cannot be filmed. The test of popular fiction — namely, its presentation in visual pictures, or let us say, the visualizing of its word-pictures — goes to pieces when applied to detective stories. The difficulties confronting a motion-picture director in the screening of a detective tale are very much the same as those he would encounter if he strove to film a crossword puzzle. The only serious attempt to transcribe a detective story onto the screen was the case of Sherlock Holmes; and the effort was made possible only by reducing the actual detective elements to a minimum, and emphasizing all manner of irrelevant dramatic and adventurous factors; for there is neither drama nor adventure, in the conventional sense, in a good detective novel.