A new exhibition at the Museum of London unravels the secrets of Sherlock Holmes

Among other things, the exhibition looks at the relationship between the detective and London. Holmes is an icon of the Victorian metropolis, a place of horse-drawn hansom cabs, dark corners, gaslight – and fog.

The Belstaff coat worn by British actor Benedict Cumberbatch in the BBC television series Sherlock. EPA/ MUSEUM OF LONDON / MATT ALEXANDER

Sherlock Holmes is among the most famous Londoners of all time. Many tourists still see the bustling city through his eyes, and seek out his address, 221B Baker Street.

It seems a logical deduction that the fictional detective’s creator, Arthur Conan Doyle, must have known the city intimately.

In fact, the historian David Cannadine said: “Conan Doyle himself didn’t spend that much time in London. When he wrote the early stories, he got the topography out of a street atlas.”

That is just one of the surprises provided by a myth-busting new Museum of London exhibition that explores a character who has been endlessly adapted while retaining his essence. He’s a cerebral sleuth, forensic scientist, drug-taking bohemian and archetypal Englishman.

Through film clips, costumes, 19th-century forensic equipment and more, it follows Holmes from an idea in Conan Doyle's notebook – at one point he was called Sherrinford Holmes – to the smartphone-toting modern detective played by Benedict Cumberbatch in the BBC TV ­series, Sherlock.

The exhibition also looks at the relationship between the detective and London. Holmes is an icon of the Victorian metropolis, a place of horse-drawn hansom cabs, dark corners, gaslight – and fog.

Fog gets a whole room of its own, lined with atmospheric images by the American photographer Alvin Langdon Coburn and other artworks, including a painting of the River Thames by the French impressionist Claude Monet.

Cannadine, who has contributed to a book that accompanies the exhibition, says Conan Doyle’s stories give a sense of the city – “The gas lamps and the clattering of horses and the fogs in Baker Street” – that is vivid, but in some ways misleading.

“He doesn’t write about the traffic jams, he doesn’t write about the smell of horse-­droppings, he doesn’t write about the filth of the pavements,” Cannadine says. “It’s a much cosier image, in a way.”

For fans, the most exciting exhibit may be a yellowing notebook showing the moment Holmes was created. It bears notes for a detective story in Conan Doyle's handwriting. The author has crossed out his original title, A Tangled Skein, and written A Study in Scarlet – the name under which Holmes's first adventure was published in 1887.

Conan Doyle, who died in 1930, probably didn’t imagine that his creation would long outlive him. He tried to kill Holmes in 1893, sending him tumbling over the ­Reichenbach Falls while grappling with his arch enemy ­Moriarty.

Readers were outraged and the author resurrected the sleuth a decade later.

The exhibition’s lead curator, Alex Werner, says Holmes endures because he was strikingly modern.

“This was a character who was using scientific methods to unmask the incredible complexity of the modern world,” Werner says. “He’s the only one who can do it. We would all like to be Sherlock Holmes.”

• Sherlock Holmes: The Man Who Never Lived and Will Never Die is at the Museum of London from Friday until April 12