The novel opens with Watson giving a first-person narrative about the contemporary events in his life. He explains that he received his Doctor of Medicine degree in 1878 from the University of London but was immediately assigned to wartime duties as Assistant Surgeon and sent to Bombay. He then traveled to Candahar. The campaign was quite unfortunate for him as he was struck by a bullet in the shoulder and had to be dragged back to British lines by his orderly. He then suffered from typhoid fever.
After he was somewhat healed, his country dispatched him to England to spend some months nourishing his health. He knew no one in London, but the money he had from the government allowed him to live a "comfortless, meaningless existence" in an expensive hotel. His money soon came close to running out and as such he sought a new living situation.
One day at the Criterion Bar he ran into an old acquaintance named Stamford; Stamford had been a dresser (a man who dressed wounds on the battlefield) at Barts. Both men were happy to see a familiar face and began chatting amiably. Watson spoke of his various misadventures and his current need for a new residence. Stamford replied that another man at the chemical laboratory where he was working had also told him that very day that he sought a roommate.
Watson inquired about the details of this man; Stamford explained that Sherlock Holmes was a very strange man and that while he was not actually a medical student and "his studies are very desultory and eccentric" he also had "amassed a lot of out-of-the-way knowledge which would astonish his professors."
Watson was pleased to hear that he potential roommate was studious and quiet, and asked Stamford to introduce them. Stamford agreed and the two of them made their way to the hospital. Along the way Stamford spoke more of Holmes; at one point curiously stated that he would bear no responsibility if the living situation did not work out for Watson. The latter was surprised at this statement, and prodded Stamford for more information. For Stamford, Holmes was too scientific and could tend toward cold-bloodedness. He did, however, have a "passion for definite and exact knowledge" and conducted strange experiments.
The two men arrived at the laboratory and entered the room where Holmes was working. As soon as Holmes saw the men entered he jumped up with glee and announced that he had found "a re-agent that is precipitated by haemoglobin." Stamford introduced Watson to Holmes, the latter remarking that Watson had clearly been in Afghanistan recently.
Holmes explained the discovery he had made, which was an "infallible test for blood stains." He demonstrated how it worked and why it was better than the old tests that existed. He was sure that several criminals who had walked free would have been jailed if this test had been used. After a few moments Stamford brought Holmes’ attention back to the situation at hand, stating that Watson was looking for a roommate. Holmes was pleased and mentioned that he had his eye upon Baker Street.
Watson and Holmes discussed their vices and shortcomings with each other; Holmes said that he "[got] in the dumps at times, and [didn’t] open [his] mouth for days on end" and Watson revealed that he was prone to laziness, weak nerves, and ungodly hours for rising. As the conversation was pleasing to both parties, they agreed to meet the following day and visit the available rooms.
As Watson and Stamford left the laboratory, Stamford remarked that he was pleased the two men got along. Watson replied that he enjoyed the mystery of Holmes, and quoted Alexander Pope: "The proper study of man is man." Stamford's response was that Watson would find Holmes "a knotty problem, though" and wagered that "he [would learn] more about you than you about him." The two said goodbye and parted ways.
Thus begins the first of many Sherlock Holmes novels and short stories. The Holmes stories have captured the literary public's imaginations like few other works of fiction. This novel establishes the relationship between Holmes and Watson, reveals Holmes' unique manner of solving crimes, and sets the precedent for how detective novels should proceed; all of these components would be utilized many times throughout the subsequent decades in Doyle's work as well as others (novelists, screenwriters) who attempted to give Holmes and Watson new life.
A Study in Scarlet is also significant for its depiction of late 19th century British life. Its evocation of the state of politics, criminal science, law enforcement, and science is edifying and useful. In fact, some scholars have made the case that Sherlock Holmes’ methods, as articulated by Doyle, have been influential to the actual development of criminal and forensic science. In an influential article from 1970, author and consulting forensics expert Stanton O. Berg attempts to explain how "the famous sleuth had a decided stimulating influence on the development of modern scientific crime detection."
Berg begins by looking at the literature that is already present on the subject. He includes analyses of the work of criminologist Ashton-Wolfe, who writes that Doyle's invented methods are present in contemporary laboratories, particularly the study of tobacco ashes. Other writers point to the study of bloodstains, footprints, and dust, as well as the usage of measuring tape, the hand lens, and the microscope. Berg avers that "perhaps the greatest evidence of the value of the Holmes stories can be found by looking to Holmes contemporaries in the fields of the police and forensic science." A French criminologist credited with being the creator of forensic science named Alphonse Bertillon from the late 19th century publicly gave credit to Holmes; Dr. Edmond Locard, also a French criminologist, credited Holmes with being influential to the development of this science. Locard wrote a scholarly paper on the study of cigar ashes after A Study in Scarlet was published.
Berg turns his attention to the "wide spectrum of scientific methods and interests utilized by Holmes in his many cases." These include the famous blood test that Holmes is performing when he and Watson first meet, study of tobacco ashes, interest in dust and dirt particles, science of fingerprinting, study of legal documents, identification of typewriters, techniques of casting, identification of bodies, and use of firearms. Berg's insightful article demonstrates that Doyle's "consulting detective" was not merely a fascinating literary hero but a figure that heralded –and provoked- a new type of criminal investigation.
This first chapter of the novel gives insight to Holmes as a character. As readers, our first impression of Holmes is the same as Watson's first impression of Holmes. He is seen as eccentric, energetic, bright, and excitable. Holmes is pleased with his discovery and self-confident about its significance and putative success and is glibly forthcoming about his own shortcomings. Watson appears to be quiet and amiable, albeit somewhat passive. He is also quite intelligent and perceptive. The two men accept each other's description of their own idiosyncrasies and conclude that living together might work. It is already apparent that they are complementary; Doyle has thus created one of the pleasing and enduring duos in literature.