There’s a charming review of BBC Sherlock on FlickeringMyth.com entitled Late to the Show — Sherlock you might want to read. I’m particularly impressed with how he manages to review the series without any spoilers.
The author does, however, consistently make the mistake of referring to Sherlock Holmes opium addiction. Sherlock Holmes never took opium in any of the stories or incarnations. He did take seven percent solution of cocaine from time to time. And the only time Sherlock ever takes morphine, in the actual stories, is when he is received a serious injury requiring stitches. In fact, using any or all of the standard definitions of addiction, the only thing Sherlock Holmes appears to have an addiction to is solving crime. Lack of interesting cases has the deleterious affect on Holmes, not his drug use. He may not even have an addiction to nicotine, if we use the stories as evidence!
Which is why I want to nail this “Sherlock Holmes was a drug addict” myth with a Buffy-sized stake through the heart (or double-barreled blast to the head of all the Sherlock Addiction Zombies, if you prefer).
Why Sherlock Holmes Is Not, Nor Has Ever Been, A Drug Addict
Addiction is the continued use of a mood altering substance or behavior despite adverse dependency consequences, or a neurological impairment leading to such behaviors.
Ad•dict•ed/Ad•dic•tion: compulsive need for and use of a habit-forming substance (as heroin, nicotine, or alcohol) characterized by tolerance and by well-defined physiological symptoms upon withdrawal; broadly : persistent compulsive use of a substance known by the user to be harmful
addicted – compulsively or physiologically dependent on something habit-forming; “she is addicted to chocolate”; “addicted to cocaine”
— The Free Dictionary
(sorry my OED is boxed up at the moment)
Note that all of these definitions refer to a dependence and most refer to an adverse or harmful result. Sherlock Holmes does not show a dependency upon any drug, even nicotine, at any time in any story. He is perfectly capably of going for long periods of time, when on a case, without so much as a cigarette or pipe. If anything, he seems more adversely affected by lack of tea. (But, of course, he is British and it is Victorian England). Dr. John Watson repeatedly mentions that the use of a seven percent solution of cocaine is taken only when Sherlock is between cases. In the very first story, A Study in Scarlet, we have this description of Sherlock by Dr. Watson:
“Nothing could exceed his energy when the working fit was upon him: but now and again a reaction would seize him, and for days on end he would lie upon the sofa in the sitting-room, hardly uttering a word or moving a muscle from morning to night. On these occasions I have noticed such a dreamy, vacant expression in his eyes, that I might have suspected him of being addicted to the use of some narcotic, had not the temperance and cleanliness of his whole life forbidden such a notion.” [Emphasis mine]
From the beginning of their relationship, Dr. Watson notes that Sherlock Holmes is not an addict, nor does he have the personal habits or behaviour of an addict. In The Sign of the Four, Sherlock does his masterful deductions about Dr. Watson’s watch being previous owned by Watson’s brother who was an alcoholic while high on cocaine. Sherlock uses the deductions to demonstrate that the cocaine has not dulled his wits.