One of the major elements of “The Red-Headed League” is the story’s representation of the dynamic urban world of late-Victorian London. During the course of the nineteenth century, London more than quintupled in population, so it was easily the largest city in the world by 1900. Due to both its sheer size and crooked, irrational layout, many people saw London as fascinating but entirely mysterious and even somewhat dangerous. Although crime rates in London at the end of the nineteenth century were almost impossibly low by modern standards, London had an aura of darkness and risk that existed simultaneously with its atmosphere of imperial might and constant energy. “The Red-Headed League” captures both sides of London, describing it as both a city of light and a city of darkness.

Doyle’s Sherlock Holmes stories illustrate the ways in which sinister mysteries unfold behind the seemingly nondescript storefronts of an average street in London. The proximity of Wilson’s pawnshop in a quiet and dilapidated square to the City and Suburban Bank on the bustling avenue highlights London’s diversity. Watson describes the difference between these two sides of the same block as being like the difference between the front of a picture and the back, one side all life and activity, the other a dark blankness. This contrast is reinforced by the different ways that Watson describes the city during the day and night. During the day, he and Holmes take the subway to Wilson’s neighborhood, walk down some recognizable streets, and finally go off to enjoy some of the high culture that urban life provides. Upon returning at night, however, Watson describes the exact same location as “an endless labyrinth of gas-lit streets,” suggesting that the dark and mysterious side of the city has come to the forefront.