Linda Stratmann is the author of the Mina Scarletti Mysteries and the Early Casebook of Sherlock Holmes series.

There are many different interpretations of Sherlock Holmes created by authors inspired by the works of Conan Doyle. They might sometimes appear to conflict, but it was my love of science fiction that made me realise that the different versions can all be valid at the same time if they exist in parallel universes. One such interpretation is that Holmes is not human but alien, or possibly even an android.
The Holmes in my books is a human, if an unusual one, but can a good case be made for him not being human? The basis of the case must, I believe, be derived from what I call ‘the canon’ — the original Holmes fiction of Conan Doyle.
So let us examine the canon and look for the clues.
Our first evidence is from Dr Watson himself. In an uncharacteristic feat of observation in The Sign of Four, he declares, ‘“You really are an automaton, — a calculating machine. […] There is something positively inhuman in you at times.”’ Holmes, he says in ‘A Scandal in Bohemia’, is ‘the most perfect reasoning and observing machine the world has seen.’
But what other clues do we have? There are many.
Clue one: An alien or android has no family tree, and Holmes is extremely cagey about his ancestors.
In ‘The Greek Interpreter’, Watson states that Holmes’s gifts for observation and deduction must come from his systematic training, and not his ancestry. Holmes agrees that this is true to some extent and reveals that his ancestors, who he does not name, were country squires who led the life ‘“natural to their class”’. However, he attributes his powers of observation to descent from a family of French artists. His grandmother was the sister of the French artist Vernet. There must, he believes, be some hereditary principle, as his brother Mycroft has the same talent.
If Holmes was an alien or android, a vague reference to unnamed county squires and an artist whose family connections could not have been easily researched would have satisfied Watson’s curiosity. Watson saw some similarities between Holmes and Mycroft, and if Holmes was an alien or android, it would suggest that Mycroft was as well.
Clue two: Holmes has strangely superhuman strength.
Holmes is not a burly man. In ‘The Red-Headed League’, ‘He curled himself up in his chair, with his thin knees drawn up to his hawk -like nose.’ Yet he obviously had a sinewy strength and was skilled in boxing, singlestick and swordsmanship.
To maintain bodily fitness over many years, regular exercise is usually necessary, but with Holmes this is not the case. ‘I have a curious constitution,’ he says in The Sign of Four. ‘I never remember feeling tired by work, though idleness exhausts me completely.’ He then heads off for a smoke.
In ‘The Adventure of the Speckled Band’we have this extraordinary incident. Holmes receives a visit from tall, broad and fierce Dr Grimesby Roylott. Roylott tries to intimidate Holmes by picking up a steel poker and bending it into a curve before flinging it down. After his departure, Holmes picks up the poker ‘and with a sudden effort, straightened it out again.’ Is that even humanly possible?
In ‘The Adventure of the Yellow Face’, Watson tells us that Holmes ‘seldom took exercise for exercise’s sake’ and that he regarded ‘aimless exertion’ as ‘a waste of energy’. Yet he also tells us that ‘Few men were capable of greater muscular effort’ and Holmes was ‘one of the finest boxers of his weight that I have ever seen.’ When there was a requirement for action, he was ‘untiring’. By the time this story was published in 1893, Conan Doyle might have sensed that he needed to explain to his readers the anomaly of a man who hardly ever exercised but excelled at physical activity. ‘That he should have kept himself in training under such circumstances is remarkable,’ says Watson, who goes on to say unconvincingly that ‘his diet was usually of the sparest and his habits were simple to the verge of austerity.’ Holmes, he adds, ‘save for the occasional use of cocaine […] had no vices.’
Clue three: Holmes uses drugs and smokes, apparently without adverse effects.
Conan Doyle introduces us to Holmes’s use of cocaine in The Sign of Four, which includes a brief single reference to the recreational use of morphine. (It is only ever used once again by Holmes, given medicinally in ‘The Adventure of the Illustrious Client’). In ‘The Adventure of the Yellow Face’,published three years after The Sign of Four,ConanDoyle obviously feels the need to dial back, perhaps after some disapproval expressed by his readers, and tells us that ‘he only turned to the drug as a protest against the monotony of existence, when cases were scanty and the papers uninteresting.’ Holmes’s heavy smoking of strong tobacco is never seen by Watson as a vice, or as something that might affect Holmes’s health.
There are numerous references in the stories to Holmes smoking heavily. In ‘The Man with the Twisted Lip’, Holmes smokes an ounce of shag tobacco while deliberating, leaving his room ‘full of a dense tobacco haze.’ In ‘The Adventure of the Engineer’s Thumb’,his before-breakfast pipe is ‘composed of all the plugs and dottles left from his smokes of the day before, all carefully dried and collected on the corner of the mantelpiece.’ If Holmes is an alien or a machine, that explains his apparent imperviousness to the harmful effects of drugs and tobacco. In later adventures, Conan Doyle does however make him more believable by showing Holmes exhausted by his burden of work as he ages. The last year in which a Holmes story is set is 1914 (His Last Bow, published in 1917), by which time he is sixty years of age, and to Watson’s eyes, has hardly changed.
Clue four: Holmes shows little emotion.
Science fiction readers and writers have compared Holmes to an android like Star Trek’s Data, lacking emotion of any kind. If he is an alien, he most closely resembles Star Trek’s coolly logical Vulcans. They have emotions but restrain them; however, they are obliged to let them all out once every seven years in a ritual called pon farr. Does this fit with Holmes’s behaviour? Does a restriction of emotions cause Holmes any stress? If he was a Vulcan, like Mr Spock, could this explain what was really happening in 1891 when Holmes rushed away to the Reichenbach Falls and did not return for three years? Did he feel the approach of pon farr and have to quit England before it took him over? If so, there would be other absences at similar intervals.
I counted back seven years and then I saw it. There are no adventures chronicled by Watson for the years 1884 and 1885. Was this because of a previous pon farr? Holmesian scholars have assumed that during these years Watson was away, perhaps in America, but there might be another explanation? Was Watson with Holmes during these absences, his account carefully crafted to conceal the truth about his friend? Looking ahead another seven years from 1892, there are no adventures dated from between January 1899 (‘The Adventure of Charles Augustus Milverton’) and June 1900 (‘The Adventure of the Six Napoleons’). There are no adventures dated 1906, or 1913. This is all supposition, of course, but the timeline is compelling.
Clue five: Holmes does not wish to marry.
Not only is Holmes averse to marriage, he appears to have no romantic or intimate connections with anyone. If he is not human, this is something he would avoid, or his masquerade as a human might be discovered. Conan Doyle is careful to avoid any suggestion of Holmes having hidden desires which would have alienated his readers. According to Watson, Holmes’s only such interest, is a woman, ‘the woman’, as he calls her, Irene Adler, whom he clearly admires but without allowing any emotions to disturb his finely balanced mind.
On what principles was the alien or android Holmes constructed or programmed?
If Holmes was sent to Earth programmed to solve crimes, he needed to be constructed from many parts. Superhuman strength and constitution. Numerous useful skills. Impervious to the ravages of smoke and drugs. A brilliant reasoning machine undistracted by emotions. The aliens who made or trained him would have studied other detectives of the era and used elements of the finest to create Holmes.
There are three main candidates:
Joseph Bell (1837–1911) was a Scottish surgeon and lecturer who advocated the importance of careful observation. Conan Doyle was a student of Bell from 1877 to 1878. Bell used his observational talents to deduce personal details about complete strangers, a skill which Holmes frequently employed.
Edgar Allan Poe’s C. Auguste Dupin is considered to be the first fictional detective, who used advanced reasoning to solve mysteries. Through observation, he is able to follow the train of thought of his companion, an ability with which Holmes astonishes Watson in ‘The Adventure of the Cardboard Box’.
Le Chevalier Lecoq, a fictional French policeman, inspired by a real criminal investigator, Eugène-François Vidocq (1775–1857). In the works of Émile Gaboriau, published in 1869, Lecoq’s methods when making a detailed examination of a crime scene, using a magnifying glass, are strongly reminiscent of Holmes’s scientific approach. In A Study in Scarlet, Holmes dismisses Dupin as ‘a very inferior fellow’ and Lecoq as ‘a miserable bungler’.
My case is complete. I have laid the facts before you. Make of them what you will.
NOTE:
There were several artists in the Vernet family but only one, Emile Jean Horace (1789-1863) fits the timeline as Holmes’s most probable great uncle. A number of Conan Doyle’s family members were artists, and a friend was a collector of Vernet.
