The Title Sequence follows a Rube Goldberg Device that drops a cage on a figurine. At first I thought it was just cool-looking, but then it occurred to me that it could be a metaphor for how Sherlock Holmes ties together seemingly meaningless scraps of information.
Another possible interpretation: A hammer smashes a porcelain head of a woman, and immediately after a cage falls and traps a small toy man. It's pretty striking symbolism once you learn about Irene.
This troper is considering two more interpretations of entire "porcelain shell smashed, man trapped".
The death of Irene broke Sherlock
With The Reveal of Irene's true identity as Moriarty, the persona of "Irene Adler" dies.
Rather than have Inspector Lestrade, the show uses Thomas Gregson. In the original Holmes stories, Gregson was locked in bitter rivalry with Inspector Lestrade ... just as Elementary, being also an updating of the Holmes stories transplanting the characters to a contemporary setting, is a rival to Sherlock.
Sherlock completely losing control in the first episode to the point of smashing Watson's car into the killer's out of sheer frustration and winding up in a cell takes on a new light when it's revealed how he lost Irene Adler. The killer in the pilot arranged for his own wife to be murdered, and Sherlock was the one who discovered her body lying in a pool of her own blood. A giant pool of blood may be all they ever found of Irene, depending on whether or not she was one of the victims whose body was never recovered.
A Freeze-Frame Bonus of Holmes' rehab report reveals that he is clinically depressed, does not take medication for it, but did see a therapist. He hasn't seen one since leaving Hemdale. Look at his actions throughout the series and many things make sense.
There's often a lot of difference between a pilot episode and the rest of the series, and this show is no exception. The biggest difference is that in the Pilot, Gregson's assistant was a guy named Abreu. Marcus Bell isn't introduced until the second episode where he replaces Abreu. The Pilot gained a lot of criticism because some of Holmes' "brilliant deductions" were things that the police would be normally expected to figure out for themselves, like Holmes finding a stray bit of glass in the corner of a room. The rest of the series has done a good job of avoiding this problem, making a good distinction between what the police could reasonably expected to figure out themselves and the sort of brilliant reasoning that only a genius like Sherlock Holmes can accomplish. Maybe Holmes finding that stray bit of glass in the Pilot was a sign that Abreu wasn't up to the job. Maybe after the Pilot, Gregson fired/transferred Abreu and replaced him with the much more competent Bell.
The name of the show. Elementary. The noncanonical, but iconic saying is "Elementary, my dear Watson." The show's title is an emphasis on the importance of Watson in Holmes' life.
For the first season finale: In the original Sherlock Holmes stories, Holmes only defeats Moriarty by pulling him over a ledge with him, with both falling to their deaths. This infamous "Fall" has been used in a lot of Sherlock Holmes adaptations, but apparently not in Elementary. Because in Elementary, it's a metaphorical fall. What do you call it when someone goes back to drugs after being sober? Falling off the wagon.
And not only that, in Elementary Sherlock's "fall" is part of a Batman Gambit designed to trick Moriarty into defeat. And it works!
As the season ending reveals, both Sherlock and Moriarty could be considered to have fallen - in love with each other. Another form of metaphorical fall.
Sherlock lives in a brownstone. A popular nickname for heroin is "brownstone". Think Holmes will one day be revealed to be a Guns N' Roses fan?
In "Child Predator", Holmes did a double take at a painting that the kidnapped child's mother was painting. Later on, it was revealed that Irene Adler was a painter.
During the flashbacks when Holmes interacted with Irene, there is a lack of people in the background, as if the only person worth seeing to Holmes was Irene. It's an interesting contrast to Joan who makes sure that Holmes is surrounded by people.
Sherlock often makes disparaging comments about obese people in the first season. Then in the second season premiere we meet his formerly fat brother Mycroft, with whom Sherlock often fought. Bad mental associations?
At the end of "Step Nine," Mycroft blows up Sherlock's belongings, including an authentic Picasso. Who else had authentic art privately? Irene. A tragic keepsake from when Sherlock thought she was dead?
"M": Moran's Wham Line: "Your girl. That was him. That was Moriarty." What if he's basically telling Sherlock that Irene is really Moriarty?
Mycroft's restaurant is named Diogenes. This is an obvious nod to the Diogenes Club that he frequents in the source material, but Diogenes was also a Greek philosopher who had a reputation for being lazy and vulgar; Sherlock frequently accuses him of being a flake, and for a man to have sex with his brother's student while visiting said brother is a rather vulgar thing to do.
The bust that is smashed in the opening sequence is female, and has a haircut that strongly resembles Moriarty's in "Heroine".
"Solve For X" revolves around "P versus NP," the most notorious unsolved problem in theoretical computer science.
In "An Unnatural Arrangement," we meet a character with the unfortunate name of "James Monroe," and British Sherlock Holmes quips "Loved your doctrine." Britain was one of the only European nations to actually be in favor of the Monroe Doctrine.
The plot of "The Long Fuse" has some horrifying implications for one character. Himali Singh learns of all the following in short order: a. Her husband Pradeep, who has been missing for four years, not only slept with prostitutes before their marriage, but filmed at least one of them. b. The prostitute Pradeep filmed was Heather Van Owen, his future boss. c. Pradeep got multiple promotions at his job by repeatedly blackmailing Heather. d. Heather finally got fed up, murdered Pradeep, and stashed his body inside the wall of his house while Himali was out of the country. That's right—while Himali dealt with the disappearance of her husband, his corpse was hidden and decomposing inside the wall of their house. For four years. No wonder the story doesn't dwell on it.
The implications behind the plot of "The Red Team." The war-game scenario that the Red Team came up with was apparently so horrifying that it was immediately classified, and one member of the team wanted to kill them all off, including himself, out of fear that one of them would crack and reveal it to someone else. Sherlock worked it out all on his own a matter of seconds. If he could do that, so could someone else...
Remember that woman Sherlock saved from Moran? Well, if Moran was merely a hitman doing the job for Moriarty, then it's likely she died anyway considering how many backup plans Moriarty has, and depending on how important her death was to whatever plot required her to die in the first place.
Not likely. It seems that Moriarty sent Moran to that woman for the sole purpose of attracting Holmes to him.
In "On the Line", how long was poor Kathy Spaulding locked in that tiny closet and tormented by a psychopath? The possibilities are horrifying...
In "The Five Orange Pipz", the corrupt FBI agent wanted to get his hands on the confiscated evidence, explicitly toy beads that turn into GHB when swallowed. GHB is often used in date rape attacks - a man in law enforcement, who would know full well what purposes the drugs might be intended for, was happy to sell something that could be used in sexual assault as long as he got his money.
Though it's in the original stories, let's talk about the Diogenes Club. Diogenes the Cynic was a man who made a virtue of poverty - which doesn't in any way describe Mycroft, or for that matter Mycroft in the original stories. While Diogenes criticized the excesses of society, Mycroft exploits them for a living. And Diogenes famously went around with a lantern in daylight looking for an honest man. That sure ain't Mycroft, who's up to his neck in secrets and lies, much like his literary predecessor. Interesting how his choice of codeword is "Paint it Black".
Speaking of which, watch the climactic scene for that episode again. Mycroft wasn't begging the Frenchmen for mercy. He was giving them one last chance.
Sherlock's Sherlock has his Homeless Network, the equivalent of the Baker Street Irregulars? What does this Sherlock have? Everyone.