LAID LOW WITH FLU, A FRIEND of mine had no head for the written word until he picked up The Collected Stories of Sherlock Holmes.His condition improved dramatically as soon as he entered that self-contained world where it is always 1895, marvelling at the readability of Conan Doyle’s 56 tales (plus four novellas).

The ingredients that make this consulting detective’s exploits as fresh today as when they were written (mostly more than a century ago) are an engaging mixture of character, incident, dialogue and plot – the last providing the structure that allows the stories to unfold.

The first person to analyse this was Ronald Knox, who initiated the mock-serious scrutiny of the “canon” in 1911 when he addressed the Gryphon Club in Oxford on Studies in the Literature of Sherlock Holmes.

Satirising the quasi-scientific textual analysis of German biblical scholars, he suggested that there were 11 elements to a Holmes plot – from the initial homely Baker Street scene, or proömion (he gave them all Greek names) through to the metamenusis(where the detective explains his reasoning) and epilogos– often a single sentence.

The future monsignor went a bit far. The typical Holmes story is a three-act drama. It starts with Holmes and Dr Watson relaxing in Baker Street (the detective might be smoking or shooting up cocaine), when someone approaches with a problem. For example, the King of Bohemia, seeking redress against the adventuress Irene Adler in the first short story, A Scandal in Bohemia. In the second act the two friends scurry across town by cab or launch into the country by train in order to reach an expertly realised scene of crime, such as Pondicherry Lodge, Bartholomew Sholto’s Norwood fastness in The Sign of Four. There, with help or often hindrance from a plodding policeman, Holmes gathers his clues. The finale comes with the detective’s measured solution to the case, followed often by him dispensing his own form of justice.

Referring in his memoirs to problems of making plots credible in short stories, Conan Doyle resolved not to write a Holmes tale “without a worthy plot and without a problem which interested my own mind”.

He managed the second part well. The thriller writer Peter James recently reminded me that detective stories are about puzzle-solving. In practically inventing the genre, Conan Doyle kept his readers riveted by conveying the enthusiasm for Victorian scientific method that came with his medical training in Edinburgh, where Professor Joseph Bell taught him to observe as the basis of diagnosis.

In his stories, he appropriated new investigative techniques such as finger printing and forensics, even if he was not always adept at the police procedural: in The Adventure of Priory School, Holmes wrongly claimed that he could tell the direction of a bicycle from its tracks.

Conan Doyle’s skill came in tweaking the basic Knoxian structure. His readers are drawn into something familiar yet they experience it as novel and exciting. He is expert at playing his two main characters off against each other, causing Watson to suggest various implausible solutions that are shot down by Holmes.

Agatha Christie may have been a more methodical plotter. But Conan Doyle was a more natural storyteller.

Conan Doyle: The Man Who Created Sherlock Holmes by Andrew Lycett
Weidenfeld, £20

Andrew Lycett appears at The Times Cheltenham Literature Festival on Sunday October 7 at noon
Call 01242 227979
www.cheltenhamfestivals.com

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