Joan Watson's Chinese name is Yun Jinsyi.
Title: The invisible hand was a term coined by economist Adam Smith in his 1776 book An Inquiry into the Nature and Causes of the Wealth of Nations. It's a metaphor to describe society benefits arising from individuals acting in their own self-interest when trying to make money.
Title: "You've Got Me, Who's Got You?" is from the 1978 movie Superman. It was said by Lois Lane in reply to Superman's line, "Don't worry, I've got you." when he caught her in mid-air after she fell from a helicopter dangling off the top of the Daily Planet.
In England and Wales, prenuptial agreements are not automatically legally binding. The courts can intercede and decide whether the agreement is fair to both parties.
The basis for the main plot is the game "E.T. the Extra-Terrestrial," an Atari game from 1982. The game's commercial failure is attributed by some to be a cause of the video game industry's crash in 1983. Over 700,000 copies were buried in an Alamogordo, New Mexico landfill and unearthed by a documentary team in 2014.
Harlan's discovery of a flaw in certain lottery systems appears to be based on the work of geological statistician Mohan Srivastava, who discovered the flaw in 2003 on tickets for the Ontario Lottery.
The book at Joan's bedside titled One Doctor - Close Calls, Cold Cases and the Mysteries of Medicine is an actual book by Brendan Reilly, M.D. The book was published by Simon and Schuster in September 2013.
Title: A clade is a technical term for an evolutionary group of organisms that includes an ancestor and all of its descendants. The doomed organisms that survived the five greatest mass extinctions in Earth's history represent the last of their clades. Paleontologist David Jablonski called these organisms "Dead Clade Walking", in homage to the 1995 film Dead Man Walking, about a death-row inmate.
Sherlock describes Devon Gaspar's message to Moriarity as written using a technique called the Ave Maria Cipher (a type of steganography). The Ave Maria Cipher uses a word, from a predetermined list, to represent a letter. The letters are replaced by the corresponding word in the message so only certain words have any significance. Only the recipient knows the hidden information is there. Devon's message is 75 letters long (not counting spaces and punctuation) so the ad in the newspaper for a used car would need to contain 75 seemingly random words, in addition to those actually about the used car.
Holmes says he bribed a chef for a room key with some rare "Swedish moose cheese". This cheese is produced by Moose House, a 59-acre moose dairy farm in Bjursholm, in northern Sweden. The cheese comes from the milk of three moose cows, named Gullan, Haelga, and Juna. It sells for $500 a pound sold mostly to upscale hotels and restaurants in Sweden.
The Latin inscription in the morgue "Taceant colloquia. Effugiat risus. Hic locus est ubi mors gaudet succurrere vitae." means "Let idle talk be silenced. Let laughter be banished. Here is the place where Death delights to succor life."
M: (to Holmes while being interrogated) He sends me coded messages on me cell phone.
If M had only just come from England and is talking to another Englishman (Holmes) then he mostly likely would have used the term "mobile" as it is called in the United Kingdom and not "cell phone".
Sherlock makes a reference to M's vintage driving gloves not being as expensive as his John Varvatos shoes. John Varvatos is an American contemporary high fashion menswear designer.
Watson's e-mail from Sherlock's father in Britain states "... you may expect your final check presently". Since the 19th century, the spelling "cheque" has been standard for the financial instrument in the Commonwealth of Nations while "check" is used for its other meanings (test, make sure, safeguard, inspection, curb, bill, etc.). In America, the spelling for all meanings is "check". Sherlock's father would most likely have used the spelling "cheque".
Goof: In the victim's apartment, the camera focuses in on bare hands playing the piano. When the camera pans around the room, Sherlock can be seen at the piano playing. When he stops playing and looks up, he points out the blood evidence with a gloved hand. As he walks away from the piano, you can see that he is wearing gloves on both hands.
When Holmes confronts Dr. Baldwin, he shows him the copy Danilo Gura took with his cell phone of Samantha Cropsey's final pathologic diagnosis with Baldwin's signature. The QR code in the photo contains contact info for Kelly Goto of gotomedia LLC, rather than that of the patient on the document. Kelly Goto is a principal and design ethnographer of gotomedia LLC who developed a fresh look and feel for the design palette of the CBScorp website. The QR code is readable with a smartphone while watching the episode in HD.
The violin piece that Sherlock Holmes plays at the end of the episode is Bach's Partita no. 2 in D minor.