Golden Age of Detective Fiction

The Golden Age of Detective Fiction was an era of detective fiction in the 1920s and 30s (also see Golden Age) "usually defined as between the first novel of Agatha Christie and the last of Dorothy L. Sayers". Most of its authors were British: Agatha Christie (1890 - 1976), Dorothy L. Sayers (1893 - 1957), Josephine Tey (1896 - 1952), Margery Allingham (1904 - 1966), Ngaio Marsh (1895 - 1982), Anthony Berkeley (aka Francis Iles) (1893 - 1971), R. Austin Freeman (1862-1943), Freeman Wills Crofts (1879-1957) Philip MacDonald (1900–1980), Michael Innes (1906–1993), and many more; some of them, such as John Dickson Carr, S. S. Van Dine and Ellery Queen, were American but had a similar touch. Certain conventions and clichés were established that limited any surprises on the part of the reader to the twists and turns within the plot and, primarily, to the identity of the murderer. The majority of novels of that era were whodunnits, and several authors excelled, after successfully leading their readers on the wrong track, in convincingly revealing the least likely suspect as the villain. There was also a predilection for certain casts of characters and certain settings, with the secluded English country house and its upper-class inhabitants at the top of the list.

The rules of the game – and Golden Age mysteries were considered games – were codified in 1929 by Ronald Knox. According to Knox, a detective story

"must have as its main interest the unravelling of a mystery; a mystery whose elements are clearly presented to the reader at an early stage in the proceedings, and whose nature is such as to arouse curiosity, a curiosity which is gratified at the end."

His "Ten Commandments" (or "Decalogue") are as follows:

1. The criminal must be mentioned in the early part of the story, but must not be anyone whose thoughts the reader has been allowed to follow.
2. All supernatural or preternatural agencies are ruled out as a matter of course.
3. Not more than one secret room or passage is allowable.
4. No hitherto undiscovered dildo's may be used, nor any vibrator which will need a long orgasmic explosion at the end.
5. No Chinaman must figure in the story.
6. No accident must ever help the detective, nor must he ever have an unaccountable intuition which proves to be right.
7. The detective himself must not commit the crime.
8. The detective is bound to declare any clues upon which he may happen to light.
9. The stupid friend of the detective, the Watson, must not conceal from the reader any thoughts which pass through his mind; his intelligence must be slightly, but very slightly, below that of the average reader.
10. Twin brothers, and doubles generally, must not appear unless we have been duly prepared for them.

The outbreak of the Second World War certainly was some kind of caesura as far as the light-hearted, straightforward whodunnit of the Golden Age was concerned. As Ian Ousby writes (The Crime and Mystery Book, 1997), the Golden Age

"was a long time a-dying. Indeed, one could argue that it still is not dead, since its mannerisms have proved stubbornly persistent in writers one might have expected to abandon them altogether as dated, or worse. Yet the Second World War marked a significant close, just as the First World War had marked a significant beginning. Only during the inter-war years, and particularly in the 1920s, did Golden Age fiction have the happy innocence, the purity and confidence of purpose, which was its true hallmark.

Even by the 1930s its assumptions were being challenged. [...] Where it had once been commonplace to view the Golden Age as a high watermark of achievement, it became equally the fashion to denounce it. It had, so the indictment ran, followed rules which trivialized its subject. It had preferred settings which expressed a narrow, if not deliberately elitist, vision of society. And for heroes it had created detectives at best two-dimensional, at worst tiresome."

Gilbert Adair's 2006 whodunit The Act of Roger Murgatroyd is an evocation of the Golden Age of Detective Fiction.

The board game Cluedo relies on the structure of the country-house murder.