THE OTHER ONE

During The Last Vow, Mycroft mentions not caring for what happened to another person that should be considered as closely related to him as Sherlock.

SIR EDWIN: If this is some expression of familial sentiment…

MYCROFT: Don’t be absurd. I am not given to outbursts of brotherly compassion. You know what happened to the other one.



This has led to speculation that Sherlock and Mycroft could have another sibling.





SISTER!

Presuming a sibling is male is an issue which was enlightened in the first episode of the show.

JOHN: And Harry’s short for Harriet.

SHERLOCK: Harry’s your sister.

JOHN: Look, what exactly am I supposed to be doing here?

SHERLOCK: Sister!

This might also be foreshadowing related to the identity of the other one.





ELIZABETH

The name Elizabeth, while not belonging to a prominent character in ACD canon, is somewhat frequently used on Sherlock, which lead me to believe that this name might belong to the Other One.

Here some possible hints/reasons:

1) It is one of the most recurring names in the show (it might even be the most recurring, but I haven’t counted):

Ella is the name of John’s therapist. It’s a short form for names starting with El, among which Elizabeth.



Beth is the name of one of the victims from A Study In Pink, which appears more than once visually onscreen as well.

As @midonz revelaed, Izzy, which is a short form of Elizabeth, is how Irene Adler is called by her friends according to the script of A Scandal In Belgravia, though it didn’t make it in the show.

There’s a journalist called Lisa in a newspaper in The Reichenbach Fall.

It’s Mary Mostan’s second name.

SHERLOCK: Today begin the adventures of Mary Elizabeth Watson and John Hamish Watson.



It’s Mary and John’s codeword.

MARY: Oh, hi, Beth! Yeah, yeah, don’t see why not.

JOHN: Actually, if that’s Beth, it’s probably for me too. Hang on. He knows we don’t have a friend called Beth. He’s gonna figure out that it’s code.



It’s Lady Smallwood’s first name.

SHERLOCK: Mr Magnussen, I have been asked to intercede with you by Lady Elizabeth Smallwood on the matter of her husband’s letters.



MAGNUSSEN: Lady Elizabeth Smallwood. I like her.



MAGNUSSEN: Tell Lady Elizabeth I might need those letters, so I’m keeping them.











2) In the Hounds of Baskerville there might be a cipher which hints at a Holmes whose initials are EH.



As the solution for UMQRA intended for the viewer might be a cipher (read UMQRA = TORCH), I ended up checking the numbers in the strings that showed up during the authorization request of Mycroft’s keycard for a numbers-to-letters cipher.

As a numbers-to-letters cipher, 5894 is deciphered as EHID.

The word ID is repeated more than once near the authorization:

JOHN: You’ve got ID for Baskerville. How?



LYONS: Your ID showed up straight away, Mr Holmes.



LYONS: ID unauthorised, sir.



So EHID might be EH ID, with EH being the initials for a Holmes, obviously not in-universe, but as a cipher intended for the viewers.

Hiding a ELIZABETH in a cipher might also be a reference to ACD canon’s The Dancing Men, in which Holmes solves a cipher knowing that the character the message was addressed to was called ELSIE.

Other possible uses of a similar cipher in series 2:





3) In Sherlock’s mind palace in The Abominable Bride, the name BETH appears capitalized in a newspaper, close to the name ISABEL, which is a Occitan form of Elizabeth, and the word LADIES.

In the newspaper Sherlock holds immediately after, a Miss Eliza (Barton) is mentioned.

There are several other meaningful capitalized word in the first newspaper page (read here), the most relevant being GIVING JAMES DANCING LESSONS and DOUGLAS (the name of the director).

The whole name Isabel Bizet has also many letters in common with the name Elizabeth.





4) In Sherlock’s mind palace in The Abominable Bride, Emelia’s referred to as BELOVED SISTER on her grave. Right next to her grave, facing the same area in the ground, there is another tombstone, which reads ALSO OF ELIZA.

In this scene these lines are said:

SHERLOCK: Mrs. Ricoletti was buried here, but what happened to the other one?

MYCROFT: Cherchez la femme.

EMELIA: Do not forget me…

Considering the theory according to which Redbeard could also a symbol for the Other One (read Redbeard is “The Other One” by wellthengameover​) and that “Cherchez la femme” could be linked to “Cherchez le chien”, there are strong reasons to suspect that these lines could be about a girl, especially a sister, buried in Sherlock’s past (they are addressed here by @deducingbbcsherlock).

The characters are specifically digging for the body of the other one and there’s an Eliza right next to where they are digging.





5) In Young Sherlock Holmes, Sherlock’s love interest is called Elizabeth, which is one of the main characters along with Watson and himself. Elizabeth eventually dies and it shapes Sherlock.



This seems similar to what they might be doing according to the theories in which the Other One is Redbeard and tied to traumatic event from childhood.

This Elizabeth has also drug-induced hallucinations in a graveyard similar to Sherlock’s in The Abominable Bride.





6) There is a non canonical Holmes sister, from a pastiche series, called Enola Holmes, whose initials are EH, same as an eventual Elizabeth Holmes.





7) Sherlock has a strong reaction after hearing Mary and John using Beth as a code word.

This is commonly attributed to him being stressed out about loosing John, but it could be hiding an ulterior meaning.





8) In Doctor Who’s The Day Of The Doctor, written by Moffat and aired less than two months before Series 3, there is a character named Elizabeth to which the phrase “other one” is applied twice, one of which in a sentence identical to a line of The Abominable Bride.



In The Day Of The Doctor:

DOCTOR 10: Elizabeth, whichever one of you is the real one, turn and run in the opposite direction to the other one.

DOCTOR 10: Which one are you? What happened to the other one?

ELIZABETH: Indisposed. Long live the Queen.

In The Abominable Bride:

SHERLOCK: Mrs Ricoletti was buried here, but what happened to the other one?









MARY AS THE OTHER ONE: INTRODUCTION

There have been some meta focusing on Mary as the Other One.

They fit with my theory of a Holmes sister called Elizabeth since it’s her second name, which might be derived by the fact that she kept her old name as a second one out of sentiment.

Meta on the matter:

@sussexbound:

@mollydobby:

Thinbeard:





The most important points of these metas are:

Mrs. Holmes calls Mr. Holmes father in front of Mary.

MRS HOLMES: Cup of tea. Now, if Father starts making little humming noises, just give him a little poke.

Mycroft’s calling Sherlock “little brother” in The Abominable Bride in Mary’s presence could be from her point of view as well;

MYCROFT HOLMES: Little brother has taken the case, of course.



Mycroft’s “mad sibling” in The Abominable Bride being gender neutral, so it might be referred to Mary;

MRS WATSON: He likes to keep an eye on his mad sibling.



Victorian Sherlock calls Mary by her first name, which would only be proper if they were closely related.

In the next paragraphs there are my own additional thoughts on the matter.





MARY AS THE OTHER ONE: A SIBLING SHOOTING ANOTHER

There would be a precedence in this show for a sibling shooting another, with Soo Lin Yao and Zhi Zhu.

There is even a revelation moment about the assassin being Soo Lin’s brother.

SOO LIN: He’s my brother.



And just after this moment we are shown a moved Sherlock fading into a gun.

Plus there are some parallels between:

Sherlock and Soo Lin:



Workaholic;



Being menaced by a veiled figure;



Involved with drugs;

As far as we know Mary might even have being involved in the Black Lotus, possibly being the assassin who shoots general Shan.

There are also some parallels between Mary and Soo Lin, like having left their past life as criminals in 5 years prior to the events shown.





MARY AS THE OTHER ONE: MARY AS REDBEARD

In Series 2 we have two adjacent episodes, one regarding The Woman and the other regarding a hound.

Sherlock shows emotional distress in both cases.

Possibly, The Woman in the first episode could be reminding him of his lost sister and the hound in the second could be reminding him of his lost dog, though none of these characters have been introduced yet.

As wellthengameover pointed out, the hound could have been created by Henry to deal with the childhood trauma of loosing his father at the hand of a close friend, so Sherlock’s dog might be a stand-in for Sherlock loosing a sibling (the Other One) during childhood, which would mean that the sister and the dog are in some measure the same entity.







In Series 3 we get introduced to some new characters: Mary, Redbeard and the Other One.







The only other time “other one” appears in the dialogue of Series 3 is during this exchange.

JOHN: See, the thing about Mary, she has completely turned my life around; changed everything. But, for the record, over the last few years there are two people who have done that and the other one is… a complete dickhead.



In this exchange:

Mary is compared to Sherlock and Sherlock is her “other one”.



After a pause, John states the other one is a dickhead, which would fit Mary’s behaviour.





In His Last Vow, we have Mycroft referencing the East Wind from Sherlock’s childhood.

The next event is Sherlock finding Mary as a shooting bride in his mind palace.

Possibly tied to “cherchez la femme”, looking for the woman, already used for a shooting bride.

The second next event is Sherlock finding Redbeard.

Possibly tied to “cherchez le chien”, looking for the dog, already used in an episode about hiding memories behind hounds.



This is commonly attributed to Mary blocking the way to John as a comforting thought, but it might even have another layer.

When Sherlock goes back some scenes later to its mind palace, he wonders about Mary in the same corridor, specifically about who Mary is.

So Mary and Redbeard might be subconsciously tied in Sherlock’s mind.



The first time that Redbeard is mentioned is at John and Mary’s wedding in The Sign of Three.

MYCROFT: Oh, by the way, Sherlock, do you remember Redbeard?

SHERLOCK: I’m not a child any more, Mycroft.



In The Abominable Bride, the bride, which is an evident mirror to Mary (an abominable bride herself), sings not to forget her and remember her.

THE BRIDE: ♪ Do not forget me, do not forget me, remember the maid, the maid of the mill. ♪







The second time Redbeard is mentioned is just a bit after a conversation about Irene Adler (which possibly reminds Sherlock of his sister), and immediately before the ghost of the Bride (Mary’s mirror) appears.

(Dog barking)

HOLMES: Redbeard?











During The Abominable Bride, “The Dog One” is also mentioned, looking surprisingly similar to “The Other One”, which might reinforce the connection between The Other One and Redbeard (and possibly the bride).







There might be some intentional wordplay connected both to Mary and Redbeard. Read Red Bird, Ginger Bread, Red Bride and Ruby Bread = Red Beard.





MARY AS THE OTHER ONE: POST MORTEM’S INTERVIEW

As @jenna221b​ pointed out, during Post Mortem’s interview Gatiss said:

GATISS: Maybe the idea of Mary working for Mycroft, it’s like a logical extension, isn’t it? And also, that thing of, you know, just having that line “Are you clear on that, Watson?” And then- oh! It’s the other one.

The “other one” is used in relation to Mary.

Plus this scene was already similar in logic to Irene calling Mr. Holmes and not actually being addressed to Sherlock, which might call for an eventual combination of these scenes into Mary being addressed as a Holmes.





MARY AS THE OTHER ONE: DOCTOR WHO REFERENCES

In addition to “the other one” being used in relation to Elizabeth…

1) there’s a background exchange in The Caretaker, an episode co-written by Moffat and aired some months after Series 3.

NOAH: Basically, you’ve to get that guy on the block and stop that other one shooting him. It’s so sick.

YASHE: I, I got that guy. That was, like, six months ago. You actually have to do is flick it that way.



This exchange is between two kids playing a videogame and is totally unrelated to the plot, so they could have said anything and the writers chose these words as fillers.

This might be related to Sherlock as in His Last Vow:

Magnussen’s building, which Sherlock enters, could be considered a block.

Mary shoots Sherlock in the building.

Sherlock has to go into a six months mission.

In the Doctor Who dialogue, the shooter is referred to as “the other one”.





MARY AS THE OTHER ONE: SIBLINGS CODING

I always got the impression that before the reveal of Mary being an assassin with her shooting Sherlock, he actually liked her, whatever her flaws, and that the relationship between the two was being developed outside of their ties with John Watson.

They are surprisingly comfortable with each other for two people who share the same romantic interest, so much that it seems to me that instead of rivals coding, we got siblings coding:

Not being jealous of each other;

They only get frustrated about sharing a romantic interest well after the wedding, when it turns out it’s not working, and even then it doesn’t seem like they are particularly jealous of each other, rather than just frustrated at a situation that cannot work.

They only get frustrated about sharing a romantic interest well after the wedding, when it turns out it’s not working, and even then it doesn’t seem like they are particularly jealous of each other, rather than just frustrated at a situation that cannot work. Joking with each other and taking each other’s sides from the first night they meet;

Having a moment alone together at the end of the first night they meet.

Here Sherlock gets something that approaches a crush filter when he first deduces Mary (a proper crush filter would be when john looks at Sherlock on the rooftop in the unaired pilot) .

She’s obviously not his crush and he should have a jealous filter instead, instead we get pretty shots with a romantic motif from his point of view.

Then Mary and Sherlock leave with the impression that they like each other;



Here Sherlock gets something that approaches a crush filter when he first deduces Mary (a proper crush filter would be when john looks at Sherlock on the rooftop in the unaired pilot) . She’s obviously not his crush and he should have a jealous filter instead, instead we get pretty shots with a romantic motif from his point of view. Then Mary and Sherlock leave with the impression that they like each other; Singling each other out for conversation when they are not alone, even when the only other person in the room is John, their love interest;



Hearing from each other without John bringing them in contact;

Being teamed up to save John and readily being a good team;



Sherlock winking at Mary;



Sherlock kissing Mary on the forehead;



Organizing a whole wedding together;



Sherlock intimidates a man who’s interested in Mary, following the logic of a My Sister Is Off Limits trope.

Sherlock’s giving Mary, during the best man speech, “the highest compliment of which he’s capable”;



Sherlock including Mary in the only vow he will ever make.

It is also my opinion that, upon rewatching the show, it would be emotionally stronger if all the people included in Sherlock’s vow where tied to him more than it first appeared rather than less.



It is also my opinion that, upon rewatching the show, it would be emotionally stronger if all the people included in Sherlock’s vow where tied to him more than it first appeared rather than less. Sherlock trusting Mary so badly that he can’t understand he’s in danger until after she shoot’s him.



Sherlock taking time to say “give my love to Mary” after acting on his vow.



Still being excessively affectionate on the tarmac, considering that, from Sherlock’s perspective, he was going to his death without a plan.



There was supposed to be a deleted scene in which Sherlock even taught Mary how to play the violin.

Finally, there are some parallels between Sherlock and Mary in his Victorian mind palace. Mary is painted as a hero, as a detective, as the one England needs, which are Sherlock’s characteristics. They still are comfortable and joke with each other. Sherlock eve goes as far as to say “For Mary, of course. Never doubt that, Watson. Never that. ”

Though he has changed his opinion of her, after all that has happened, there is still a level on which he likes her and feels they are similar.

Mary in Sherlock’s modern mind palace is depicted as shady, which given the circumstances is more appropriate.

In both cases there is still not jealousy between the two of them, but rather frustration not directed at each other for both being John’s love interest.





MARY AS THE OTHER ONE: LINKS TO OTHER THEORIES

Mary being Sherlock sister tangentially fits with some other theories of mine:

Series 3 being based on Swan Lake, with Sherlock as the White Swan and Mary as the Black Swan (read here and here).

In this story there are two characters that look alike, but one is the hero and the other is the villain.

In this story there are two characters that look alike, but one is the hero and the other is the villain. Un Dollaro Bucato being referenced in His Last Vow (read here).

In this story two siblings are put one against the other without them knowing, ending up in one shooting the other.

In this story two siblings are put one against the other without them knowing, ending up in one shooting the other. Mary possibly having past and future parallels to Dorothy Gale from The Wonderful Wizard of Oz.

She could have being a young Holmes sibling plucked by the East Wind (Dorothy was taken away by a tornado) and might have shared Redbeard as a pet (Dorothy has a pet dog) (read here).

She could have being a young Holmes sibling plucked by the East Wind (Dorothy was taken away by a tornado) and might have shared Redbeard as a pet (Dorothy has a pet dog) (read here). Mary possibly being associated with the figure of Cassandra, as in His Last Vow there is the mention of a soccer player probably called Cassandra (the name might have been misheard) shooting a ball and missing the target, just like Mary did (read here).

If Mary turned out to be the Other One, there would be some similarities between her and Cassandra.

Here’s a brief summary of the relevant points as described on Wikipedia.

Cassandra was clever, but considered insane and seen as a liar by her family and everyone else.

She instructed her twin brother Helenus in the power of prophecy. Like her, Helenus was always correct in his predictions, but people actually believed him.

She was only believed when she claimed that Paris was her abandoned brother.

So we have: 1) Cleverness, 2) Being a liar or only being believed so in Cassandra’s case, 3) Predictions, which could be akin to deductions, 4) The presence of a brother (a twin in Cassandra’s case) with similar talents and 5) The revelation of a lost brother.





MARY AS THE OTHER ONE: MARY’S MOTIVATION

ACD Canon Mary Morstan is looking for her lost father (before discovering that he’s dead).

They could have translated this into Mary looking for her whole lost family in BBC Sherlock, as the motivation driving her character.

This would be compliant with the Wonderful Wizard of Oz parallels theory as well, as Dorothy is trying to find a way back to her family, after a wind has taken her away.





MARY AS THE OTHER ONE: OTHER HINTS CONCERNING THE NAME ELIZABETH

Here’s some other hints limited to the relation between Mary and Elizabeth.

Elizabeth is Mary’s fake middle name, she could have kept it out of sentiment.

The grave which is being searched in The Abominable Bride is that of a bride, a role which is relevant for much of Mary’s screen time.

So we have the grave of a bride, which says BELOVED SISTER, next to another tombstone saying ALSO OF ELIZA, HIS WIFE.

If Mary was to be the Other One, she would be both sister and wife to the main characters.

Probably a coincidence, but these journalists also have variations of John and Mary’s second names, which might mean their second names have some significance.



Sherlock mistakes Mary for Elizabeth Smallwood, since both wear Claire de la Lune.

If Mary’s real name is Elizabeth, maybe that’s the reason Lady Smallwood got it as her first name, to reinforce the fact that it’s not just a second name for Mary.

REFERENCES

Ariane DeVere’s Sherlock Transcripts

Chakoteya’s Doctor Who’s Transcripts