"Wanna Woo-woo?"

"... I have a plot for a book that I intend to write some day that I believe gets over the perfect murder most adequately. ... In that book I shall show that the police and detectives are utterly baffled and that at last the murderer himself has to come forward and tell how he committed the crime. I will have him to do this out of a pure sense of bravado and love of the dramatic, or possibly motivate it by showing that he is suffering from an incurable disease and is going to die soon anyway."

"Sounds like a lot of baloney to me," snorted Lang.

— Eric Heath, Murder of a Mystery Writer

"Fire's a damned sight worse," he muttered. "Cripes, my head's like a pumpkin! It's always at the back of my mind."

— Ellery Queen, The Siamese Twin Mystery

The amateur detective, or AD as he is affectionately known to insiders, is the most popular crime-solving creation among the writers of detective fiction. Beginning with Jacques Futrelle's Professor F. X. Van Duesen, "The Thinking Machine," in this country, and, somewhat later, Chesterton's Father Brown in England, the AD has seen more bloodletting, faced more peril, and unraveled more mysteries than all professional detectives, public and private, combined.

The AD can be of either sex, of any age; can possess any quirk or specialized knowledge and be of any profession (or no profession at all). The AD roster includes doctors, lawyers, merchants, thieves; little old ladies with a homicidal eye and fusty professors with very large brains; bored young men of wealth and breeding, and derelicts on Skid Row; newspaper reporters, poets, playwrights, fiction writers, nonfiction writers, unpublished writers, songwriters, and insurance underwriters; salesmen, bankers, Indians, artists, magicians, priests, nuns, gamblers, teachers, scientists, sports figures, photographers, publicans — and a hundred more. The AD can be hard-boiled, soft-boiled, half-baked, well-pickled, or sugar-coated. He/she can use fists, guns, wits, half-wits, innocence, guile, luck, pluck, deduction, guesswork, or any combination of these to solve a case and bring an evildoer to justice.

What the most enduring of the amateur detectives seem to have in common is an abiding interest in criminology, an encyclopedic knowledge of trivial and/or esoteric facts, a Sherlockian intelligence, a penchant for withholding evidence from the police (but never from the reader, no matter how obliquely it is couched), and such endearing qualities as the enigmatic smile, the gimlet eye, the curled lip, the disarming grin, the sharp retort, the clever pun, the cryptic remark, and the perfect squelch. Consider the great ADs of mystery fiction: Father Brown, Dr. Fell, Ellery Queen, Lord Peter Wimsey, Reggie Fortune, The Great Merlini, Miss Marple, Perry Mason, John J. Malone, "The Old Man in the Corner," Mr. and Mrs. North, Miss Hildegarde Withers. When these ladies and gentlemen embark on a case, it is bound to be a memorable one.

The same is true of the great ADs on the other side of the qualitative coin.

The earliest of these is Joseph Rouletabille, a Parisian reporter who solves a number of cases in the early 1900s narrated by his Watson, Sainclair, and created by French writer Gaston Leroux. The first, The Mystery of the Yellow Room (1907), is well known and also considered by some — John Dickson Carr, the grand master of the "impossible crime" story, was one — to be among the finest "locked-room" mysteries ever penned. This may be true, if one reckons solely on ingenuity of plot; but if one takes into account stilted writing, nonexistent characterization, incredible coincidences, and a welter of disguises, aliases, and red herrings — plus such other implausibilities as the fact that Rouletabille, already a successful journalist, is not much older than sixteen when he solves the mystery of the yellow room — Leroux might seem better placed, or at least equally well placed, at the opposite end of the mystery spectrum.

From this standpoint, his most (or least) accomplished work is the second of the Rouletabille cases, The Perfume of the Lady in Black (1909). Chief among its noteworthy aspects is a preposterous plot in which the villain of The Mystery of the Yellow Room, a brilliant former detective named Frédéric Larsan, who was supposedly killed off in that book, returns alive and in disguise (à la Sherlock Holmes) to commit a new locked-room murder, this one involving the use of false-face and a tricked-up wardrobe. There are also more aliases, red herrings, and coincidences, some crudely worked out motivations, a final "revelation" that Rouletabille is the illegitimate son of Larsan, and such artful prose as:

He rushed to the canal, sobbing, and, with a prayer, uttered as much to the Lady in Black as to God Himself, threw himself into the water. Happily, in his despair, the poor child had forgotten that he knew how to swim.

He had mocked her, even while the tears had streamed down his cheeks. I could never have believed that Rouletabille could have been so cruel or so heartless — or, even, so ill-bred!

The first of the notable ADs on the American front is Professor Herman Brierly, who appears in four novels by Will Levinrew published in the late twenties and early thirties. Brierly is an elderly research scientist of the following description: "small, exquisitely formed body, not over five feet tall; tiny hands and feet, bushy, snow-white hair, bushy black brows over dark blue eyes so deeply sunken in their sockets as to seem jet black; high, fresh complexion rarely found except in infancy." Brierly is also a superintellect of a crabby, somewhat egotistical nature that puts him in a class with his obvious role model, Philo Vance. His stock-in-trade is solving crimes through "scientific deduction," which is a masking euphemism for the fact that he unravels the most convoluted, Van Dineish plots with a minimum of detection and a maximum of obscure textbook science and pathology.

The most interesting of his cases is Murder on the Palisades (1930), in which a number of people are murdered in a gloomy old mansion on the New Jersey Palisades, across the Hudson River from New York City. Because Levinrew was a devotee of Van Dine, this novel, like his others, is chock full of footnotes, interminable question-and-answer sessions, befuddled cops, bizarre occurences, and clues of the esoteric variety (the first few letters of the Hebrew alphabet, for example, play an important, if rather unbelievable,...