Sherlock Holmes, the private detective based in 221b Baker Street, London, is regarded as the private investigator stereotype. His innovative method of forensic investigation from the late 19th and the early 20th is based solely on accurate observation and purely logical conclusions.

Sherlock Holmes is described as a man who pursues a variety of interests after completing his studies in chemistry. He thereby attempts to ensure himself the kind of detective work that meets his expectations. His methods are considered very factual, accurate and effective. Later on, Holmes is described playing his Stradivarius violin as a leisure activity. The detective is portrayed as financially independent, which makes it possible for him to spend several weeks without a paid job at his residence and being able to pursue his interests.

He is described as a tall and slender man. His outfit is that of a city dweller of the middle class, whereby always wearing a red and gold robe in the evenings.

Holmes has a brother, named Mycroft Holmes, whom he considers to be more talented and intelligent than himself. However, his brother has a lazy character, which prevents him from becoming a detective. Mycroft Holmes is a political consultant for the government service and a founding member of the Diogenes Club in London.

Sherlock Holmes calls himself a consulting detective He sees his work as an additional service or an alternative to the judicial police. Most of the stories are told from the perspective of Holmes' friend, Dr. John H. Watson, who is also shown to live in 221b Baker Street at times. The scope of the famous detective includes fighting crime, investigating thefts, searching for missing people and shedding light on apparently inexplicable deaths.

In addition to these, the stories deal with topics such as secret societies, criminal societies, threats and blackmail, threats to public safety, and much more. The decisions taken by Sherlock Holmes are, naturally, always different from those of the police. He thereby continuously rejects their conclusions and attempts to explain his own to the authorities.

Sherlock Holmes' cases often start with a client seeking advice and contacting the private investigator for his help and expertize. Scotland Yard, represented by Inspector Lestrade, is also assisted by the successful investigator on a case-by-case basis. The detective often begins his investigation even if there is no commission involved, simply because his interest was sparked by interesting events. This may be due, for example, to an article he read in a newspaper or news shared by his friend, Dr. Watson. Holmes often becomes involved in the investigation when a solution seems almost impossible.

The investigative and educational work of Sherlock Holmes lay at the heart of all stories. Not all stories about the famous detective involve fighting against crime. Quite the contrary - the author, Sir Arthur Conan Doyle, once estimated that about a quarter of all stories do not revolve around fighting crime, because no crime was actually committed.

A new case is usually distinguished by an extraordinary mystery or crime, focusing on its resolution. This often overlaps with the past of the client, since he can no longer find his way through the mess and turns to the famous detective for help.

Against the will of his mother, who was a big fan of the London-based detective, the author of the series’ hero decided to have him die during a battle with his fiercest opponents Professor Moriarty. The showdown of the story took place at the Reichenbach Falls near Meiringen in Switzerland. It led to a fight between Holmes and Moriarty, in the course of which both plunged in the waterfalls, and, due to the geological features of the Reichenbach Falls, the recovery of the two was impossible.

Sherlock Holmes’ death led many London-based readers of the novels to tie a black ribbon around their upper arm in order to express their grief, and they cancelled their subscriptions to the Strand magazine, where many of the stories about the most famous of all detectives have appeared.

However, another story about the famous detective appeared several years later. Through a friend of his, Sir Arthur Conan Doyle’s attention was called upon the legend of a ghost dog. Intrigued, the author wrote the story "The Hound of the Baskervilles", which was dated before he passed away.

Later, however, Doyle wrote a book in which he stated that Holmes was struggling with Professor Moriarty and managed to free himself from his grip at the last minute so that only he had passed away. With this trick, he had opened the way to write more stories about the private detective Sherlock Holmes.

Many stories about the detective Sherlock Holmes appeared not only in the form of books, but also as audio books, in film or television and are now available on DVD or as computer games.