The decline in canonical references to cocaine after the 1890s may reflect changing public opinion. By the early 20th century, popular sentiment had turned against narcotics. Reports of addiction and overdose became more frequent, and medical journals began to reassess the drug’s value. By the time of His Last Bow (1917), the tone of the stories had become more sombre and nationalistic, and Holmes had retreated to the Sussex Downs to keep bees. There, one imagines, the stimulation he once sought from chemical means had been replaced by the quiet order of apiary life. It is tempting to read this retreat as a metaphor for balance: the restless mind finding, at last, a sustainable rhythm. From a narrative perspective, Holmes’s cocaine habit performs a number of functions. It creates dramatic contrast between activity and idleness, between intellectual euphoria and psychological despair. It also reinforces Holmes’s identity as a man living on the margins of society—not quite part of the world he protects. Unlike other detectives of the period, Holmes is not drawn into domesticity, nor does he seek public acclaim. He operates from a private code of engagement, and when that code fails—when no clients call and no puzzles remain—he turns inward, and the cost is high. It is also possible to view the cocaine use as a literary device that reflects the broader cultural tensions of the fin de siècle. The late Victorian period was characterised by a simultaneous faith in progress and anxiety about its effects. Science was advancing, but moral certainties were in decline. The great institutions—Empire, Church, Monarchy—still held sway, but cracks had begun to show. In this context, Holmes stands as both a product and a critique of his time. His brilliance embodies the triumph of reason, but his reliance on cocaine suggests that reason alone cannot sustain the human spirit. He is a figure of immense capability who, when denied the friction of the world, turns to chemistry to preserve his edge. There is an important distinction to be drawn between how cocaine functions as a real drug and how it functions symbolically within the Holmes stories. In practical terms, cocaine is a stimulant that produces temporary alertness and a sense of euphoria. Its effects on mood and concentration are short-lived, and the risk of dependence is well-documented. But within the Canon, cocaine represents more than its pharmacological effects. It stands for the danger of the mind unmoored from its purpose. It is what happens when intellect outpaces opportunity, when talent exceeds the society that surrounds it. It is not so much a character flaw as a structural problem: Holmes lives in a world that cannot keep up with him. That the habit fades over time is, in this light, a sign of narrative resolution. The cases become more satisfying, the work more purposeful, and perhaps Watson’s influence more deeply felt. Holmes does not undergo a radical transformation, but he changes enough. The syringe returns to its case, the violin becomes more frequent, and the stories shift their emotional register. If not peace, there is at least equilibrium. Sherlock Holmes’s cocaine habit is an integral part of his character and of Conan Doyle’s broader literary project. It reflects the psychological cost of genius, the medical culture of the 1880s, and the philosophical dilemmas of modernity. The Canon does not preach or condemn. Instead, it presents a portrait of a man in tension with himself and his time—seeking order in chaos, stimulation in stillness, and clarity in a world too slow for his mind. In the end, the seven-percent solution is not just a drug. It is a metaphor for the burden of brilliance, and for the quiet despair that sometimes lies behind the cold logic of the world’s first consulting detective.