A Study in Emerald is a Hugo Award-winning short story by Neil Gaiman, essentially an Intercontinuity Crossover between Sherlock Holmes and the works of H.P. Lovecraft. Written in the style of a classic Holmes pastiche, this story, roughly following the plot of the first Holmes novel A Study in Scarlet, finds a brilliant consulting detective and his new flatmate investigating the gruesome murder of a member of the royal family.Can be read here for free, in nifty newsprint format. Which we highly recommend you do before proceeding to the trope list, which contains spoilers.And also just because it's awesome.
The name Vernet is a nod to a minor line from the Holmes story "The Adventure of the Greek Interpreter."
The Sigerson alias was also used as such by Holmes in the period between the events of "The Final Problem" and "The Adventure of the Empty House".
"John (or perhaps James) Watson" is a reference to Arthur Conan Doyle's notorious inability to keep Watson's first name straight. Call it an incontinuity nod.
Likewise, there's a similar nod to the text's disagreement about where on his body Watson was injured in Afghanistan. Study in Scarlet placed it on his leg, later stories said his shoulder. In A Study in EmeraldMoran, i.e., the "fake" Watson, was wounded in his shoulder, while the real Watson was wounded in his leg.
Moran refers to Watson as "The Limping Doctor" until Holmes and Watson's names are revealed at the end.
Indeed. I hate to say this, but it is my experience that when a doctor goes to the bad, he is a fouler and darker creature than the worst cut-throat.
Subverted, in that the average reader is quite likely to agree with the killer, Dr. Watson, that his actions were right and necessary.
This is also either a Continuity Nod or Mythology Gag, in that the line is originally used to describe Dr. Roylott in The Adventure of the Speckled Band: "When a doctor does go wrong he is the first of criminals."
The narrator refers to the "savages" of Afghanistan (both human and Eldritch Abomination) who are unwilling to see the reasonableness of being ruled by their betters in London or even Moscow.
Did You Just Have Tea With Cthulhu: Early in the story, the protagonists are briefed by the Queen who while oddly voiced, speaks English and talks lucidly, and is nice enough to heal the narrator's injury. She seems decent enough if you ignore the strong implication (probably certainty) that she and her relatives like to Mind Rape people every once in a while and will probably wipe out humanity pretty soon.
Medical Monarch: Queen Victoria is able to ease the narrator's constant pain from a wound he received from an Eldritch Abomination in Afghanistan. Of course, she's probably related to it.
Names to Run Away From Really Fast: All plays on the titles of Lovecraft characters. The Czar Unanswerable (The Unnameable), the Black One of Egypt (Nyarlathotep), Parent to a Thousand (Shub'Niggurath).
Noble Top Enforcer: Lestrade, the detective, the narrator and Prince Albert all seem like decent people.
Perspective Flip: Kind of. Moriarty and Moran are the "good guys" and Holmes and Watson are the antagonists. However, while the reader probably ends up seeing the latter as still being heroic, Moriarty and Moran actually are well-intentioned in this setting despite their allegiance to Eldritch Abominations.
Royally Screwed Up: Played for kind of dark humor in that the Queen's relatives seem to be the usual debauched and reckless sort that the human Victoria had (and probably many/most monarchs have), but it's taken Up to Eleven, given what they are.
Serial Numbers Filed Off (In-Universe): The plays they see concerning the mistaken identity between identical twins and the girl who sells violets are, respectively, Shakespeare's The Comedy of Errors and The Little Match Girl by Hans Christian Andersen with a few details changed.
The latter of which makes perfect sense, seeing as the "hero" of the third play gained his status by beating a Christian priest to death with a crucifix. The Great Old Ones are not in the slightest friendly to the old religions.
Sherlock Scan: Mostly played straight with the Great Detective, but subverted/parodied in the scene where he recognizes that the murder victim is a member of the German royal family... by the number of his limbs and the green shade of his blood.
Shout-Out: With the exception of the first one, which introduces a theater troupe that will feature in the plot, each of the advertisements between chapters.
"Victor's Vitae", manufactured by Victor von F., promises to restore life to the dead... nether regions.
Staring Down Cthulhu: The consulting detective, when he meets Victoria, doesn't seem at all intimidated.
That's What I Would Do: The detective tells the narrator that he figured out how the murderers got away based on the fact that he would have done the same thing. An early moment of foreshadowing that, in an Alternate Universe, he is the villain.
Title Drop: In the description of the crime scene.
Twice Told Tale: The ending can be hard to follow unless you're relatively familiar with the Sherlock Holmes canon. (The story doesn't require a similarly close knowledge of the Cthulhu mythos, but it doesn't hurt.)
Weird Moon: It's bright red thanks to the Old Ones.
Worthy Opponent: The Great Detective and his equally clever antagonist take this attitude toward each other.
Writing Around Trademarks: The narrator refers to the detective as "my friend." This sort of thing is common in professionally published pastiches, and the legal status of the Holmes characters is turbulent. It's actually because the narrator and his friend are NOT Watson and Holmes.