"A Case of Identity" is one of the 56 Sherlock Holmes short stories written by Sir Arthur Conan Doyle. It is the third of the twelve stories collected as The Adventures of Sherlock Holmes. It was first published in The Strand Magazine in September 1891.
- "It is my business to know things. Perhaps I have trained myself to see what others overlook."
- ―Sherlock Holmes in A Case of Identity
- "You did not know where to look, and so you missed all that was important."
- ―Sherlock Holmes in A Case of Identity
Set in 1888, the story revolves around the case of Miss Mary Sutherland, a woman with a substantial income from the interest on a fund set up for her. She is engaged to a quiet Londoner who has recently disappeared. Sherlock Holmes's detective powers are barely challenged as this turns out to be quite an elementary case for him, much as it puzzles Dr Watson.
The fiancé, Mr Hosmer Angel, is a peculiar character, rather quiet, and secretive about his life. Miss Sutherland only knows that he works in an office in Leadenhall Street, but nothing more specific than that. All his letters to her are typewritten, even the signature, and he insists that she write back to him through the local Post Office.
The climax of the sad liaison comes when Mr Angel abandons Miss Sutherland at the altar on their wedding day.
Holmes, noting all these things, Hosmer Angel's description, and the fact that he only seems to meet with Miss Sutherland while her disapproving youngish stepfather, James Windibank, is out of the country on business, reaches a conclusion quite quickly. A typewritten letter confirms his belief beyond doubt. Only one person could have gained by this: Mr James Windibank. Holmes deduces that "Angel" had "disappeared" by simply going out the other side of a hansom cab.
After solving the mystery, Holmes chooses not to tell his client the solution, since "she would not believe me... There is danger to him who snatches a delusion from a woman." In this, however, he can be accused of not fulfilling his professional duty for which he was paid - namely, to investigate the matter to which she set him, provide her with the results and let her decide what to do with them. Holmes does advise his client to forget "Mr Angel"; Miss Sutherland refuses to take Holmes advice and vows to remain faithful to "Angel" until he reappears-for at least ten years.
Critic Peter Marrow wrote: "As it stands, the story's ending makes no sense - forcing one to try to look for something left unsaid. Far from Windibank's conduct not having broken any law, he has left himself wide open to Miss Sutherland suing him for breach of promise and certain to win - as the proposal had been made by a man who was already married, and her step-father at that. Yet Holmes does not advise to his client this obvious course. This could, however, make sense on the assumption that Windibank was not only interested in Miss Sutherland's money but also in her person; that the bogus engagement covered an illicit and effectively incestuous action which might have been mutual, even if not consummated; that Miss Sutherland on at least some level knew all along who "Hosmer Angel" truly was; and that Holmes was acting in her best interest in not bringing all this out in the open and avoiding a traumatic and shattering breakup of her family in the glare of sensational publicity. It can be assumed that Doyle's readership in the 1890s was aware of these undercurrents and tended to agree with Holmes decision."
One may wonder whether Dr Watson disagreed with Holmes behaviour in this matter, since he published an account of the whole story a few years later. Holmes conclusions would then surely find their way to Miss Sutherland as well, though she would hardly be glad to find that the whole story had been turned into entertainment for the masses. Watson's description of herself, including references to her "preposterous hat" and "vacuous face", would probably not be much appreciated either.
Holmes predicts Windibank will continue a career in crime and end up on the gallows. "There is danger for whom taketh the tiger club."