MIRRORED STRUCTURE
Having set this foundation for the final conflict, the writers went into integration overdrive, selecting each element of the individual episodes and orchestrating them so they would set up and mirror the steps Sherlock needed to take so as to reach his thematic destination: being ”a good man”
NAMES AND FICTIONS AS THEMATIC MOTIFS
“Sherlock” employs two primary motifs throughout Season 4 - Names and Fictions - as symbols of its overall theme. Besides being used to show and reinforce the thematic universality of these two symbols, their repetition is used to ‘take the curse off’ any qualms a viewer might have about the story’s climactic reveals. By establishing them as regularly occurring - as seemingly commonplace - the viewer is led to easily accept the twist at the season’s end - that Sherlock suffers from corrupted memories, all revolving around a single name - rather than the viewer dismissing that twist as a far-fetched contrivance.
THE POWER OF LOVE
The transformative power of a single thing - love - is the theme of the series. Love has the power to give meaning (“context”) to everything. It changes everything. This is the lesson Sherlock has to learn: how something so simple, so familiar, so seemingly inconsequential - something “hidden in plain sight” - can so totally transform the world without one recognizing its ability to do so.
WHAT’S IN A NAME?
To concretize this singular power, the writers created “Redbeard” - ‘a name Sherlock instantly recognizes’. A name which, to him, is innocent, benign and seemingly of little importance. Yet that single name ultimately ‘tears his world apart’ - i.e. transforms it - and him - completely.
Of course the power of love to transform the world is not limited to Sherlock alone. It is a universal principle. It applies to all human beings. As such, the writers mirror their concretization of that power across the whole of the season. Not only is Sherlock’s life transformed by a single name (Redbeard), but numerous lives are thusly transformed by particular names:
Mary - by AGRA
Ajay - by AMO (ie the code name LOVE)
Sherlock - by NORBURY
Faith - by ANYBODY
Eurus - by NOME (i.e. No One)
And of course, as previously indicated, these are all callbacks to the episode HotB, specifically two names: HOUND, which transformed the victim’s life; and MAGGIE, which solved the entire mystery.
HOUND
As noted above, HOUND is the original source for the idea that a single name can transform a person’s life. It is an acronym (like AGRA) for the names of a group of scientists. And mistaking that name as a thing (an actual hound, rather than a person) is the source of the mystery. As Sherlock says, the choice of the word/name Hound is “why I took the case”. Basically, the writers have retroactively made this an instance of foreshadowing - which is a neat trick.
MAGGIE
Also as previously noted, this is a subtle callback, made near the beginning of T6T, to the HOUND case. The missing Thatcher statue leads Sherlock’s subconscious to alert him to….something - something he can't quite identify yet; what he calls a “premonition” but which is really a recollection of his own past. As such, Sherlock recognizes it as the approach of evil: “something wicked this way comes”. And, combined with that recognition, we get the overt introduction of watery death imagery.
AGRA
This is another callback - to “His Last Vow” (HLV S3E3). AGRA is the name that changed John’s life completely - for what it revealed about Mary. He discovered that his seemingly innocent wife was once an “assassin”.
Additionally, in T6T, the name AGRA comes back to haunt Mary, transforming her life this time.
AMO
Established for the first time in T6T is the name AMO. The writers chose this name for its double meaning: being the code name for Lady Smallwood -and- being the Latin word for LOVE (thus making the name both the abstraction and the concretization of the theme at the same time - another neat trick). And the writers use this dual thematic context to great effect, applying it to the theme of empathy vs ego:
Love, in the form of Lady Smallwood, is used to save lives. Love selflessly saves other. In this case, Love seeks to rescue hostages from terrorists.
However, false love, in the form of Vivian Norbury, is used to murder. Love of self, rather than of others, is used to destroy. In this case, AMO transformed the life of Mary’s colleague Ajay, leaving him to be tortured senselessly for years. In other words, because there was actually no Love, Ajay was abandoned to “hell”.
NORBURY
This is the name which transforms Sherlock’s life at the end of T6T. It is Sherlock recognizing, in himself, the monster he is fighting in others - his petty, destructive ego. The deadly consequences and subsequent transformation he experiences due to his realization that he, too, is a “monster” - are so profound, he informs Mrs. Hudson that if she ever sees him being too full of himself again, she merely need say the name Norbury to him. He will understand instantly.
That is the transformative power of a single name.
ANYONE
This is the name Eurus brings to Sherlock’s attention in her guise as Faith in TLD. It serves three transformational purposes:
First, it completely changes the life of “Faith”. As with HOUND, Sherlock takes her case because “your whole life turned on one word...but HOW can that word be a name - a name you instantly recognized that tore your world apart.” “Okay, well, how?” she asks, to which Sherlock replies “No idea. Yet.”
Next, it’s the clue, for Sherlock, which is the solution to the mystery of Smith: that he is a serial killer.
And, finally, it is also Eurus’ clue for Sherlock, serving as a key to unlock the name in her own mystery - i.e. NOME.
NOME
This is the name Eurus references (“No One”) as the key to unlocking her song’s meaning (it is the “context” for the song) which leads Sherlock to ‘save her soul’.
REDBEARD
This, of course, is the name which all the others mirror and foreshadow. It is the name which Sherlock instantly recognized and which tore his world apart’. It is the name - and the transformation - to which the series had been consciously building since Season 3.
WHY NAMES?
The reason names were chosen for all these instances of transformation is also thematic. Love (empathy) does not identify a thing. It identifies a relationship - how one feels about another person. It is people, not things, who give existence its meaning. And people have names. Thus it is thematically important that the concretization of the transformative power of love is manifested, not by words (which describe things) but by names (which identify people).
That's more great writing.
Amusingly, and for emphasis, the writers did a reversal of this motif in TFP. In Eurus’ Coffin Game, Sherlock is told he must guess a name from a clue - that clue being “I Love You”, printed on the coffin’s name plate.
Even the writers’ humor is thematic.
And, just to tell the audience how important names are to the season, the writers broke with a long standing tradition. Previously, before each season aired, the writers would give one word clues as to the nature of each individual episode. For the last season, however, they explicitly stated they were departing from that practice and would instead be giving a single name as the clue for each episode: THATCHER, SMITH, SHERRINFORD.
Choosing names rather than mere words as clues for each episode reveals how important the writers consider names to be in regard to the season’s theme.