Doyle has Holmes solve a case that involved a now discarded Mormon doctrine in the first adventure of this great detective.
Sherlock Holmes may be the greatest fictional detective ever conceived, although some scholars would argue Edgar Allan Poe's Dupin may have a better claim to this title. Doyle's creation is better known. In his first case, Holmes would encounter the dark side of a uniquely American religion.
Sherlock Holmes's first case would have him encountering the darker side of early Mormonism. The most famous anti-Mormon group, the Utah Light House Ministry, felt that Doyle's A Study in Scarlet was enough of a condemnation of Mormonism that they included the full text of the story on their web site.
A Study in Scarlet takes the reader back to an event relevant to the mystery that Holmes must solve that occurred 20 to 30 years before the events in the story unfolded. Sherlock Holmes never does get to meet any actual Mormons and the person who hires him in A Study in Scarlet left the church. The depiction, however, is a somewhat accurate but fictionalized account of the Mormon church under the leadership of Brigham Young.
Doyle's depiction of Utah is more interesting because it gives the reader an idea of the public perception of the Mormons at the time, rather than an accurate portrayal of how things took place.
The case that Holmes solves revolves around the now discarded Mormon doctrine of Blood Atonement and a polygamous marriage the second Mormon prophet tried to force on the daughter of Holmes' client. The author who does not wish to spoil the story for anyone who had not read it suggests that the reader pick up an anthology of Arthur Conan Doyle's Sherlock Holmes stories and read a A Study in Scarlet for the full details of Holmes' first case.
While many people will say that Arthur Conan Doyle's portrayal of the Mormons under Brigham Young is not totally inaccurate, today Sherlock Holmes might be surprised to find that the American counterpart of Scotland Yard, the FBI, heavily recruits Mormons, according to an article that ran in Time Magazine.
Resources:
“A Study in Scarlet.” Arthur Conan Doyle. The London Times. 1898.