Note: Thanks so much to . A lot of this chapter required direct transcription from the episode and this saved me a lot of gruelling hours.

Also, it's worth noting that I've condensed/cut a lot of things out of Sherlock's speech and I've rewritten moments to include the OC's. I tried to keep a lot of it, but I'm also relying on readers knowing this episode well to almost 'fill in the blanks', otherwise this chapter would be the size of a novel!

In saying that, this chapter is still massive! I hope you guys don't mind that. Anyone who follows this story knows that I try not to copy a lot of moments directly from the show and I only transcribe when necessary – If you know the episode well and don't want to read the speech then you can skip the section between these: '**III**'

Thanks so much for your continued support of this story. I appreciate every single read, favourite, follow and I love reading your reviews. So thank you again!

III

It had been weeks since the nights out that had left everybody feeling worse for wear. Margaux had noticed a shift since that night. A change in dynamic. In the weeks that followed, Sherlock would speak to her as if she were an acquaintance, keeping conversation shallow and polite. When they would come together, it was evident that his focus was Vaughan. He would come to her flat, he would spend time with his son and then he would leave. At first it seemed as though he had simply forgotten how to interact with other people, but it wasn't long before she noticed that she was the only one receiving the brunt of his cold, distant regard.

John and Sherlock stood near the entrance of the church. It was a warm, bright Spring day. The blossom tree had shed soft pink petals across the grounds in the gentle breeze, and there was a hum of excitement as the guests arrived, congratulating John with a handshake or a hug, before heading inside. Margaux and Vaughan climbed out of a taxi and made their way down the path of the church. She was wearing a pale blue dress that nipped in at her waist and flowed to just below her knees, the sleeves were long and sheer with delicate floral embroidery, and her hair was loosely pinned at the nape of her neck. Vaughan was wearing a suit, specially made to match the groomsmen, even down to the small grey top hat on his head. Sherlock picked him up, asking him questions about his suit, while Margaux gave John a hug.

"I won't ask if you're nervous because that's a stupid question." She smiled.

John nodded with a laugh. Margaux glanced up at Sherlock who was concentrating on their son. Purposely ignoring her.

"I'll leave him with you until you're ready to come in," she said. "Congratulations, John." She smiled, giving him a kiss on the cheek and venturing inside the church to find a seat.

The ceremony was beautiful. An aura of love and happiness surrounded the couple as they were pronounced husband and wife. They ran outside hand-in-hand to the sound of wedding bells, the guests circling the path, cheering and clapping for them. They stood together smiling for photographs, John in his smart suit, Mary glowing and ethereal in her gown. Margaux placed confetti in Vaughan's hand and they threw it together as John and Mary stepped into the middle of the crowd. She watched as Sherlock and Janine stood together for photographs. Taking note of the way Janine leaned in to talk to him. She wondered what they were saying.

"The famous Mr Holmes," said Janine. "I'm very pleased to meet you. But no sex, okay?"

Sherlock's eyes widened. "Um, sorry?"

Janine let out a laugh. "You don't have to look so scared. I'm only messing. Bridesmaid, Best Man… It's a bit traditional." She punched his arm playfully.

He grimaced. "Is it?"

"But not obligatory."

"If that's the sort of thing you're looking for… the man over there in the blue is your best bet. Recently divorced doctor with a ginger cat. A barn conversion… And a history of erectile dysfunction." He blinked as he assessed his observations. "Reviewing that information, possibly not your best bet."

"Yeah, maybe not."

"Sorry, there was one more deduction there than I was expecting."

"Mr Holmes," she began, taking his arm. "You're going to be incredibly useful."

III

The reception venue was a pretty country hall surrounded by gardens and stone fountains. The walls were laced in ivy, the tall arched windows painted white, allowing light to pour in from outside. Sherlock, John and Mary stood outside greeting the guests as they arrived. Being pleasant was laborious, how did people manage to be like that all the time, Sherlock thought.

"David!" Mary called out, reaching her arms out to hug the man approaching them.

He leaned away, awkwardly avoiding the hug with a nervous laugh. "Mary, congratulations." He held her hands briefly. "You look, um, very nice." He quickly moved on to shake John's hand, leaving Mary confused. "John, congratulations. You're a lucky man."

"Thank you," John replied.

"Um, er, David, this is Sherlock," said Mary.

Sherlock gave him a disingenuous smile.

"Er, yeah. We've um, we've met," said David, looking down at the floor.

Assessing the guests wasn't an official Best Man role. But it was one Sherlock felt could benefit them, and one he found incredibly interesting. David was Mary's ex. Whenever she tweeted, he would respond within five minutes regardless of time or current location, suggesting he had her on text alert. In all his Facebook photographs, Mary would take centre frame whereas John would be partly or entirely excluded. He was still in love with her. This was enough for Sherlock to downgrade him to a casual acquaintance – putting the fear of god in him in the process.

David stammered, struggling to find anything to say. Instead, he just walked inside, waving feebly at them as he went.

"Here they are! Hello," said Mary excitedly as Margaux and Vaughan approached.

They hugged, giving a kiss on each cheek.

"Congratulations, the ceremony was beautiful, I'm so happy for you!" said Margaux as she moved on to John, giving him the same hug and double kiss.

"We're so glad to have you here, both of you," said John as he crouched down to Vaughan's level. "You looking after your mum today?"

Vaughan nodded and they high fived.

Margaux stepped aside to Sherlock.

"Hi," she said.

"Hello, welcome."

"Thanks…" she gave an awkward laugh. "You look very nice."

"As do you."

Mary and John looked at each other, sharing the same confused expression.

Margaux leaned towards him so she could speak quietly. "Is everything alright?"

"Dr Cave, you're holding up the queue."

Her stomach dropped in both hurt and embarrassment. She scooped up Vaughan and quickly went inside without uttering another word.

"Doctor. Cave?" Mary scowled before another guest quickly came and stole her attention.

III

The photographer wandered around the hall, capturing shots of people talking and drinking. He approached Molly and her fiancé Tom who stopped kissing to smile for the camera. Next, he snapped Mrs Hudson at her table with Mr Chatterjee. Nearby sat Greg Lestrade, drinking alone, raising his glass solemnly. The photographer turned to snap Margaux sat with Vaughan on her knee. She pointed to the camera, trying to get Vaughan to look into the lens, and smiled.

Sherlock watched from across the room. His jaw clenched, lips pursed tightly.

"He's nice," said Janine as a waiter passed them.

He inhaled deeply. "Traces of two leading brands of deodorant, both advertised for their strength, suggestive of a chronic body odour problem manifesting under stress."

"Okay, done there. What about his friend?"

Sherlock turned to where she was looking to see another waiter in the kitchen.

"Long term relationship, compulsive cheat."

"Seriously?"

"Waterproof cover on his smartphone, yet his complexion doesn't indicate outdoor work. Suggests he's in the habit of taking his phone into the shower with him, which means he often receives texts and emails he'd rather went unseen."

Janine smiled adoringly at Sherlock. "Can I keep you?"

He glanced back over at Margaux who had noticed them talking. She was watching them carefully, her face twisted in what Sherlock could only decipher as worry. He saw this as an opportunity. "Do you like solving crimes?" He asked, making sure she was still watching.

"Do you have a vacancy?"

Margaux watched as Sherlock and Janine parted ways, catching his eye as he walked across the room. She smiled at him and gave him a gentle wave. He averted his gaze and continued walking to the back of the hall.

**III**

A clinking glass echoed through the hall, causing conversations to disperse.

"Pray silence for the best man," said the head waiter.

The room burst into applause as Sherlock rose to his feet. The speech had proved a bigger rival than some of the criminals Sherlock had put away. But now was the time, whether he was ready or not.

"Ladies and gentlemen, family and friends... and, erm... others. Er... w... A– also..."
"Telegrams," John murmured.

"Right. Erm…" He patted his pockets before noticing the telegrams on the table in front of him. He cleared his throat. "First thing's first. Telegrams." He picked them up and showed them to the room. "Well, they're not actually telegrams. We just call them telegrams. I don't know why. Wedding tradition. Because we don't have enough of that already, apparently."

He read the telgrams half-heartedly. Rushing through them and making small quips and sarcastic comments. John sighed at him, Mary rolled her eyes. There was a small rumble of laughter amongst the guests while Molly watched on admiringly and Margaux covered her eyes with her hand.
"John Watson," he gestured towards John. "My friend, John Watson. John. When John first broached the subject of being best man, I was confused. I confess at first I didn't realise he was asking me. When finally I understood, I expressed to him that I was both flattered and… surprised. I explained to him that I'd never expected this request and I was a little daunted in the face of it. I nonetheless promised that I would do my very best to accomplish a task which was, for me, as demanding and difficult as any I had ever contemplated. Additionally, I thanked him for the trust he'd placed in me and indicated that I was, in some ways, very close to being... moved by it." He paused. "It later transpired that I had said none of this out loud."
John let out a laugh.

Sherlock reached into his pocket and retrieved his cue cards, clearing his throat as he began to sift through them. "Done that, done that, done that bit, done that bit, done that bit. Hm… I'm afraid, John, I can't congratulate you. All emotions, and in particular love, stand opposed to the pure, cold reason I hold above all things." His eyes involuntarily darted to Margaux for just a second. Long enough for her to notice and drop her head. "A wedding is, in my considered opinion, nothing short of a celebration of all that is false and specious and irrational and sentimental in this ailing and morally compromised world." A sense of discomfort travelled around the hall. "Today, we honour the death-watch beetle that is the doom of our society and in time, one feels certain, our entire species. But anyway, let's talk about John."
"Please," said John desperately.

"If I burden myself with a little help-mate during my adventures, it is not out of sentiment or caprice; it is that he has many fine qualities of his own that he has overlooked in his obsession with me."

Greg laughed again, Margaux kicked him under the table.
"Indeed, any reputation I have for mental acuity and sharpness comes, in truth, from the extraordinary contrast John so selflessly provides. It is a fact, I believe, that brides tend to favour exceptionally plain bridesmaids for their big day. There is a certain analogy there, I feel."
Janine looked up at him, almost offended by his words.

"And contrast is, after all, God's own plan to enhance the beauty of his creation… Or it would be if God were not a ludicrous fantasy designed to provide a career opportunity for the family idiot."

Mary and John began to cringe, hiding behind their hands as the guests watched on in horror.

"The point I'm trying to make is that I am the most unpleasant, rude, ignorant and all-round obnoxious arsehole that anyone could possibly have the misfortune to meet. I am dismissive of the virtuous, unaware of the beautiful," he made a point of looking down at Janine as he spoke. "And uncomprehending in the face of the happy. So if I didn't understand I was being asked to be best man, it is because I never expected to be anybody's best friend. Certainly not the best friend of the bravest and kindest and wisest human being I have ever had the good fortune of knowing."
The guests relaxed into their seats. Mary smiled at John, proud to be his wife.

"John, I am a ridiculous man, redeemed only by the warmth and constancy of your friendship. But, as I'm apparently your best friend, I cannot congratulate you on your choice of companion. Actually, now I can. Mary, when I say you deserve this man, it is the highest compliment of which I am capable. John, you have endured war, and injury, and tragic loss," he leaned in "So sorry again about that last one." He straightened up again. "So know this: today you sit between the woman you have made your wife and the man you have saved – in short, the two people who love you most in all this world. And I know I speak for Mary as well when I say we will never let you down, and we have a lifetime ahead to prove that."

Mrs Hudson began to cry, holding a tissue to her nose while Molly wiped a tear from her eye. Margaux sat back in her chair, she was proud of him.
"If I try and hug him, stop me," said John.

"Certainly not," Mary replied.

"Ah, yes. Now on to some funny stories about John..." he looked up to see the room full of guests snivelling and whimpering into their napkins. "What's wrong? What happened? Why are you all doing that? John?"

"Oh, Sherlock!" said Mrs Hudson.

"Did I do it wrong?"

John stood up. "No, you didn't. Come here." He pulled him into a hug before the room began to applaud.

"I haven't finished yet."

"Yeah, I know, I know."

"So, on to some funny stories about John… If you could all just cheer up a bit, that would be better. On we go. So, for funny stories," he took out his phone. "One has to look no further than John's blog; the record of our time together. Of course, he does tend to romanticise things a bit, but then, you know, he's a romantic." He gave a slight wink at the couple. "We've tackled some strange cases: The Hollow Client, the Poison in the Plant. We've had some frustrating cases, 'touching' cases, and of course I have to mention the elephant in the room. But we want something ... very particular for this special day, don't we? The Bloody Guardsman."

He told the story of the case in great detail; the soldier with the stalker, the shower full of blood, John saving the young man's life. With each word he shocked, confused and perplexed the guests.

"Private Bainbridge had just come off guard duty. He'd stood there for hours, plenty of people watching, nothing apparently wrong. He came off duty and within minutes was nearly dead from a wound in his stomach, but there was no weapon. Where did it go? Ladies and gentlemen, I invite you to consider this: a murderer who can walk through walls, a weapon that can vanish. But in all of this there is only one element which can be said to be truly remarkable. Would anyone like to make a guess?" The room was silent. "Come on, come on, there is actually an element of Q and A to all of this." Still, no one spoke. "Scotland Yard, have you got a theory?"

Greg looked up, staring at him blankly.

"Yeah, you. You're a detective, broadly speaking. Got a theory?"

"Er, um, if the, uh, if the, if-if-if if the blade was, er, propelled through the, um… grating in the air vent... maybe a-a ballista or a, or a, or a catapult. Erm, somebody tiny could-could crawl in there. So yeah, we're loo... we're looking for a… dwarf?"

"Brilliant."

"Really?"

"No."

Lestrade sighed and lowered his head.

"Next!" said Sherlock.

Margaux inhaled, opening her mouth as if she were about to speak.

"Not you, you'll get it right away, that's no fun," he said, shooing her with his fingers before moving on.

"He stabbed himself," Molly's fiancé whispered.

"Hello? Who was that? Tom…"

Tom stood up awkwardly. "Um... attempted suicide, with a blade made of compacted blood and bone; broke after piercing his abdomen. Like a meat... dagger."

A few of the guests sniggered. Molly sat next to him, mortified.

"A meat dagger," Sherlock repeated.

"Yes."

"Sit. Down," said Molly through gritted teeth.

He sat down immediately.

"There was one feature, and only one feature, of interest in the whole of this baffling case, and quite frankly it was the usual. John Watson. Who, while I was trying to solve the murder, instead saved a life. There are mysteries worth solving and stories worth telling. The best and bravest man I know, and on top of that, he actually knows how to do stuff… Except wedding planning and serviettes. He's rubbish at those."

"True," John interjected.

"The case itself remains the most ingenious and brilliantly-planned murder – or attempted murder – I've ever had the pleasure to encounter; the most perfect locked-room mystery of which I am aware. However, I'm not just here to praise John, I'm also here to embarrass him, so let's move on to some–"

"No-no, wait, so how was it ... how was it done?" Lestrade interrupted.

"How was what done?"

"The stabbing."

Sherlock looked down awkwardly for a few moments, then raised his head. "I'm afraid I don't know. I didn't solve that one. That's... It can happen sometimes. It's very, very disappointing."

Margaux began to open her mouth again. Sherlock raised a finger as if to say: 'zip it'. She rolled her eyes and took a swig of wine.
"Embarrassment leads me on to the stag night. Of course, there's hours of material here, but I've cut it down to the really good bits."

He told the story of the stag night, keeping it light and entertaining, avoiding the intrusive thoughts of the morning after that kept trying to force their way in. He told the story of the woman that came for help; inspecting the flat of her ghostly lover while completely intoxicated. He recalled her story of The Mayfly Man, his flawed deductions, falling asleep on the shaggy rug which he later threw up on. He recalled the landlord threatening to call the police. 'Oh, no, this is a famous detective. It's Sherlock Holmes and his partner, John Hamish Watson.' She had said as they stumbled around the apartment 'clueing for looks'.

"Married. Obvious, really," he continued his speech. "Our Mayfly Man was trying to escape the suffocating chains of domesticity. And instead of endless nights in watching the telly or going to barbecues with awful dreadful boring people he couldn't stand, he used his wits, cleverness and powers of disguise to play the field. He was–" He looked around the room to see that people where losing interest; confused, bored. "On second thoughts, I probably should have told you about the Elephant in the Room. However, it does help to further illustrate how invaluable John is to me. I can read a crime scene the way he can understand a human being. I used to think that's what made me special. Quite frankly, I still do. But a word to the wise: should any of you require the services of either of us, I will solve your murder, but it takes John Watson to save your life. Trust me on that – I should know. He's saved mine so many times, and in so many ways." He held up his phone. "This blog is the story of two men and their frankly ridiculous adventures of murder, mystery and mayhem. But from now on, there's a new story. A bigger adventure. Ladies and gentlemen, pray charge your glasses and be upstanding…" He picked up his glass while the guests stood up with theirs. The photographer stepped forward with his camera at the ready. "Today begins the adventures of Mary Elizabeth Watson and John Hamish Watson. The two reasons why every single one of us is–" He stopped speaking. His blue eyes widening as the champagne glass slipped from his hand.

The photographer began taking pictures, the bright flash bursting over and over again in his face. He was thinking back to the woman on the stag night. She said 'John Hamish Watson.' She said that. Hamish. How did she know John's middle name? He never told anyone because he hated it so much, taking years to even confide in Sherlock. Then something else echoed in his mind. Something else she said. 'Enjoy the wedding.' She knew about the wedding. More importantly, she had seen a wedding invitation. He began to deduce; barely one hundred people had seen the invitation. The Mayfly Man saw five women. For one person to be in both groups, could be a coincidence, but the universe was rarely so lazy. So someone went to great lengths to find out something about the wedding; lied, assumed false identities, which meant criminal intent. Which meant… The Mayfly Man.

"Here today," he finally finished, seconds before the glass shattered on the floor. "Oh, sorry, I…"

"Another glass, sir?" said the waiter.

"Thank you, yes. Thank you, yes."

Margaux watched carefully; he was acting odd, something was wrong. She lifted Vaughan into her arms, holding him tightly.

"Ladies and gentlemen, people tell you not to milk a good speech; get off early, leave 'em laughing. Wise advice I'll certainly try to bear in mind. But for now..." Sherlock leapt over the table, making the guests gasp in shock. "Part two. Part two is more action-based. I'm gonna... walk around, shake things up a bit."

He began to walk around the hall, taking a good look at each person as he walked past.

"Who'd go to a wedding? That's the question. Who would bother to go to any lengths to get themselves to a wedding? Well, everyone Weddings are great! Love a wedding."

"What's he doing?" Mary asked John quietly.

"Something's wrong," John replied.

"And John's great, too! Haven't said that enough. Barely scratched the surface. I could go on all night about the depth and complexity of his... jumpers. And he can cook. Does a... thing –thing with peas…"

John and Mary exchanged a confused glance as Sherlock continued to examine each guest carefully.

"Might not be peas. Might not be him. But he's got a great singing voice, or… somebody does. Ahh, too many, too many, too many, too many!" He noticed he was frightening people. He unclenched his jaw and smiled. "Sorry. Too many jokes about John! Now, er... Where was I? Ah, yes... Speech!" He pointed at the top table. "Speech. Let's talk about…" then it clicked. "Murder."

John sighed while Mary frowned, glancing over at Margaux with wide, confused eyes. Margaux shrugged and shook her head.

"Sorry, did I say 'murder'? I meant to say 'marriage'. But, you know, they're quite similar procedures when you think about it. The participants tend to know each other, and it's over when one of them's dead. In fairness, murder is a lot quicker, though. Janine!"
Janine stared at him in shock.

He stood behind a man who was sitting at one of the tables. "What about this one? Acceptably hot? More importantly, his girlfriend's wearing brand-new uncomfortable underwear and hasn't bothered to pick this thread off the top of his jacket, or point out the grease smudge on the back of his neck. Currently, he's going home alone. Also, he's a comics and sci-fi geek. They're always tremendously grateful; really put the hours in," he laughed.

He turned his attention to Lestrade. "Geoff, the gents." He jerked his head towards the door. "The loos, now, please."

"It's Greg," replied Lestrade.

"The loos, please."

Lestrade's phone beeped. "Why?" He asked as he took it out of his pocket.

"Oh, I don't know. Maybe it's your turn," said Sherlock, gesturing to the door again.

Lestrade looked down at his phone. Sherlock Holmes (1).

'Lock this place down.'

"Yeah, actually, now you mention it…" he said, standing up and beginning to walk out.

"Sherlock, any chance of an end date for this speech? Got to cut the cake," said John.

Sherlock gave a manic smile, dancing down the aisle towards the top table. "Oh! Ladies and gentlemen, can't stand it when I finally get the chance to speak for once." He glared directly at John and spoke his last two words clearly. "Vatican Cameos."

John straightened in his chair.

"What did he say? What's that mean?" asked Mary.

"Battle stations. Someone's going to die," said John.

"What?!"

John placed his hand on hers, willing her to stay calm and quiet.

"You." Sherlock pointed at John. "It's always you. John Watson, you keep me right."

John stood up as Sherlock walked towards him. "What do I do?"

"Well, you've already done it. Don't solve the murder. Save the life." He took a sharp breath and turned back to the guests. "Sorry. Off-piste a bit. Back now. Phew! Let's play a game. Let's play Murder."

"Sherlock…" Margaux whispered.

"Imagine someone's going to get murdered at a wedding. Who exactly would you pick?"

"I think you're a popular choice at the moment, dear," said Mrs Hudson, unamused

"If someone could move Mrs Hudson's glass just slightly out of reach, that would be lovely. More importantly, who could you only kill at a wedding? Most people you can kill any old place. As a mental exercise, I've often planned the murder of friends and colleagues." He rubbed his hands together. "Now, John, I'd poison; sloppy eater, dead easy. I've given him chemicals and compounds, that way, he's never even noticed. He missed a whole Wednesday once, didn't have a clue. Lestrade's so easy to kill, it's a miracle no-one's succumbed to the temptation. I've got a pair of keys to my brother's house. I could easily break in there and asphyxiate him… If the whim arose."

"He's pissed, isn't he?" Tom mumbled to Molly.

Molly stabbed a fork into the back of his hand.

"Ow!"

"So, once again, who could you only kill here?" Sherlock continued. "Clearly it's a rare opportunity, so it's someone who doesn't get out much. Someone for whom a planned social encounter known about months in advance is an exception. Has to be a unique opportunity. And since killing someone in public is difficult, killing them in private isn't an option. Someone who lives in an inaccessible or unknown location, then. Someone private, perhaps, obsessed with personal security. Possibly someone under threat. A recluse, small household staff."

At this point, he knew who the victim was. He had narrowed it down so carefully that he was almost certain. He took a name card from a table and wrote a note on it, placing it in front of one of the guests.

"There is another question that remains, however, a big one. A huge one. How would you do it? How would you kill someone in public?"

The man lifted the card and read the note. 'It's You.'

"There has to be a way. This has been planned."

Vaughan began struggling in Margaux's lap. She shushed him and tried to keep him still but he continued to fidget.

Sherlock turned to look at him. "What is it, Vaughan? What's your theory?"

"Oh don't be ridiculous, Sherlock," said Mrs Hudson. "He's a baby."

Vaughan began lifting his little jacket up over his head, hiding himself for a moment before revealing his face again. Sherlock held his hand up at Mrs Hudson as he stepped closer to Vaughan.

"What's that, son?" He straightened up and turned to the rest of the guests. "My son, everybody, isn't he great," he turned back to him. "What are you trying to tell me?"

"He's playing peek-a-boo, Sherlock. That's what toddlers do," said Margaux.

Sherlock continued to watch as Vaughan hid himself under his jacket. Then it clicked. He gasped and straightened up, his eyes wide. The invisible man with the invisible knife. The one who tried to kill the guardsman.

"You're a genius, Vaughan," he said. "Ladies and gentlemen, there will now be a short interlude." He picked up a glass. "The bride and groom!"
"The bride and groom," the guests mumbled in utter confusion.

Sherlock turned sharply to John. "Major Sholto's going to be murdered. I don't know how or by whom, but it's going to happen."

**III**

No one expected the wedding to become a crime scene. Not even Sherlock. On a day that was supposed to be about love and happiness, the bride and groom found themselves outside a hotel room door, begging John's friend to let them save him. Major Sholto had been taken away in an ambulance. He was going to be okay.

Within a few hours, it was as if nothing had happened. The wedding party was in full swing, and Sherlock found himself in the foyer, dancing the waltz with Janine. He was counting the steps out loud, frustrated with her for not keeping up. They stopped dancing.

"Just… hold your nerve on your turning," he said.

"Why do we have to rehearse?"

"Because we are about to dance together in public and your skills are appalling." He smiled at her.

She laughed. "Well, you're a good teacher."

"Mm."

"And you're a brilliant dancer."

"I'll let you in on something, Janine."

"Go on then," she whispered flirtatiously.

"I love dancing. I've always loved it."

"Seriously?"

"Watch out," he said, looking around to make sure no one was there, before performing a perfect pirouette.

"Oh, whoa!"

He cleared his throat. "Never really comes up in crime work but, er, you know, I live in hope of the right case."

"I wish you weren't… whatever it is you are."

"It's not the first time I've heard that."

III

Margaux stood at the edge of the dancefloor, smiling as she watched John and Mary dance their first dance. They waltzed together, gazing into each other's eyes like they were the only two people in the room. At the side of the room, Sherlock played the violin. A song he had composed especially for them; gentle and light. Margaux turned her attention to him, admiring how he swayed as he played, his eyes fixed on the newlyweds with pride. She felt a sudden pang of sadness, yearning to know what had changed between them, why he couldn't even bring himself to look at her anymore.

John dipped Mary backwards, making her gasp. They giggled and kissed each other as the song came to an end. The room broke into applause directed at the couple, while Janine whooped for Sherlock. Margaux watched him; the way he looked at Janine as she cheered, the way he picked up his buttonhole flower and threw it across the room to her, the way he glanced in Margaux's direction to see if she'd noticed. She didn't look away, instead she pleaded with him silently, begging him to stop this.

"Ladies and gentlemen," Sherlock began, "Just, er, one last thing before the evening begins properly. Apologies for earlier. A crisis arose and was dealt with. More importantly, however, today we saw two people make vows. I've never made a vow in my life, and after tonight I never will again."

Margaux looked down at the floor before pushing her way through the crowd to the tables at the back of the room.

"So here, in front of you all, my first and last vow. Mary and John: whatever it takes, whatever happens, from now on I swear I will always be there. Always. For all three of you." He stopped for a moment, tripping over his words. "Er, sorry. I mean, I mean two of you. All two of you. Both of you, in fact. I've just miscounted. Anyway, it's time for dancing. Play the music again, please, thank you." The disco lights began to flash and the music began to play. "Okay everybody, just dance, don't be shy. Dancing please! Very good!" He stepped down off the stage and walked over to John and Mary. "Sorry, that was one more deduction than I was expecting."

"Deduction?" asked Mary.

"Increased appetite, change of taste perception, and you were sick this morning. You assumed it was just wedding nerves. You got angry with me when I mentioned it to you. All the signs are there."

"The signs?"

"The signs of three."

"What!?"

"Mary I think you should do a pregnancy test. Wh– the… the statistics for the first trimester are–"

"Shut up," John interrupted. "Just shut up."

"Sorry."

"How did he notice before me? I'm a bloody doctor!"

"It's your day off."

"It's your day off!"

"Stop panicking."

"I'm not panicking."

"I'm pregnant, I'm panicking!" Mary interrupted.

"Don't panic," said Sherlock. "None of you panic. Absolutely no reason to panic."

"Oh and you'd know about that. You've never had to bloody panic," John gestured to Margaux sitting at the back of the room alone, rocking Vaughan who was sleeping in his pram.

"Yes, I would. You're already the best parents in the world. Look at all the practice you've had!"

"What practice?" asked John.

"Well you're hardly going to need me around now you've got a real baby on the way." Sherlock's mouth curved into a smile.

John laughed and pulled them both into a hug.

"You alright?"

"Yeah," said Mary breathlessly.

"Dance," Sherlock instructed.

"Hm?"

"Both of you, now, go dance. We can't just stand here. People will wonder what we're talking about."

"Right."

"And what about you?" Mary asked tearfully.

"Well we can't all three dance. There are limits," John joked.

"Yes there are," said Sherlock.

"Come on, husband. Let's go."

And with that, they were gone. Dancing amongst the crowd under the flashing lights. Sherlock lowered his head, avoiding eye contact with people who may try to pull him into a dance. He looked over at Margaux, only once, before turning away and beginning to look for Janine. She was dancing nearby, his buttonhole flower pinned to her dress. She smiled at him, he smiled back and began to walk towards her, stopping immediately when she pointed to the man she was dancing with, followed by a big thumbs up. She turned away and continued to dance.

He walked up to the stage and picked up the sheet of music he had written for Mary and John. He folded it, placed it in an envelope and left it on the stand before stepping down and pushing through clusters of dancing guests to the exit.

III

Outside, the warm spring day had turned into a cold, breezy night. He flicked up the collar of his coat and began to walk, the vibrant party growing softer with every step across the dark, quiet garden.

"Where are you going?" A trembling voice echoed behind him.

He stopped and turned slowly to see Margaux standing in the middle of the lawn.

"I'm leaving," he said. He looked over at the disco lights coming from the manor. "Where's Vaughan?" He asked.

"He's asleep in his pram, Molly's watching him."

"Good. Go inside and enjoy the rest of the party." He turned and continued to walk.

"Don't walk away from me," her voice grew slightly louder – irritated.

He looked at her again; her hair blowing in the cold breeze, goose bumps forming on her arms and legs.

He sighed. "It's cold–"

"I'm fine," she said with a shiver.

He took off his coat before walking towards her and draping it around her shoulders.

"Why are you leaving?" she asked.

"I watched them get married, I solved a case, I played them their song. There's nothing left for me here now."

"Nothing left? Sherlock, wh–" Her voice shook before trailing off quietly.

Neither of them spoke again for a long time. Usually in those silences, they were speaking without words. But not this time. This time they were simply looking at each other, allowing the quiet to engulf them.

"Jay…" Sherlock finally said, almost whispering.

Margaux's brows furrowed in confusion as her eyes darted around his face. "Wh– I…" She was dumbfounded. "Is this what this has all been about?"

He didn't answer. Instead, he tried to leave again.

"Stop. Walking. Away from me!" her assertiveness caught them both off guard. "Tell me! Is this why you've been giving me the cold shoulder?"

"I'm… removing myself from the situation–"

"Cut the bullshit, Sherlock." She pointed her finger at him. "May I remind you, it was you who rejected me, then slept with me, then pushed me away again." She stepped closer to him, pushing her finger into his chest as she spoke. "I solved cases for you, I was there for you the second you asked me to be… I was almost killed because of you. Then you pretended to die. So I grieved for you, raised your son by myself, and then I let you back into both of our lives when you decided it was a good idea to come back." Her eyes began to water, her voice croaking as she fought the urge to cry. "You flirt with me when you're bored, you say the most hurtful things like it's nothing, you treat me like a stranger when it suits you, and now… Now, you have the audacity to be upset that I met someone else? Well, let me tell you something, Sherlock. You don't get that luxury. You're not entitled to that."

He looked down at the floor, his jaw clenched, unable to speak. She slipped off his coat and pushed it into his hands before stepping away from him.

"I didn't sleep with him," she said. "Not that it's any of your business."

"Marg–"

"I wanted to, though; I took him back to my flat, we had wine, we talked, we kissed. But when it came down to it, I couldn't do it… Because he wasn't you." She wiped away the tears that were trickling down her face, crossed her arms over her chest to shield herself from the cold. "You don't want me, but you don't want anyone else to have me either, right? Well there you go. It seems as though I don't want anyone else to have me either."

She walked back inside quickly, feeling the sobs forcing their way up her throat, the tears mixing with her makeup and stinging her eyes. She didn't look back once. But she knew Sherlock – she knew he wouldn't care enough to chase her.

III

The hotel room was small and cosy. In one bedroom, Vaughan was sleeping soundly in the travel cot. Margaux covered him with his blanket, kissed her hand and touched it against his forehead. She left the door open a crack before returning to her own bedroom. She slipped off her dress and climbed into bed, trying to calm down enough to fall asleep by inhaling and exhaling deeply. A knock on the door startled her. She got up immediately and pulled a hotel robe around her before opening the door with a shaking hand.

"Hi there, Margaux Cave?" A young hotel employee stood smiling on the other side.

She felt as though she could cry all over again. But instead she held it inside, smiling politely. "Yes?"

"Your phone was found in the hall downstairs, someone identified it as yours." She handed her the phone.

"Oh. Thank you so much, that's really kind of you."

The girl nodded and left down the corridor. Margaux closed the door, her hand barely leaving the handle before there was another knock. She opened it again. But this time, it was him. She stepped to one side gesturing for him to come in, but he stayed put, standing on the other side of door.

"Hi…" She said timidly.

"I just came to tell you I'm sorry," he began. "My behaviour was unjustified. Above all else, you are the mother of my child and you deserve to be treated with a level of respect that I did not display."

She took a deep breath. "Thank you."

Sherlock nodded. "Goodbye."

"Goodbye."

And with that, he left. Margaux closed the door slowly behind him before sitting on the edge of her bed and dropping her head into her hands. She was exhausted; the type that couldn't be cured by sleep. She should have asked him to stay.

After a few moments, there was another knock on the door. Softer, more hesitant. She opened it again, stepping aside as she had done before, and this time he walked straight into the room. She closed the door and leaned back against it, watching him pace the carpet. He wanted to speak but something was stopping him. The two cogs were fighting again, she thought.

"I fear…" he began quietly, struggling to let the words leave him. "I fear I may become lost in you…"

She looked at him in amazement, understanding how hard it had been for him to say those words. "I've been lost in you for years," she finally replied. "Maybe it's where we're meant to be."

He stared at her for a moment before approaching tentatively. She remained still with her back against the door, careful not to move in case she scared him away, like a deer scarpering at the sound of snapping branches. He took a final step, bringing them face to face, and brought his hand to her cheek. It was cold, almost trembling as he brushed his fingers over her cheek, her jaw, and weaved them into her hair. Finally, he leaned down and kissed her.

It was as if their bodies had never forgotten the other's touch; the way her palms curved perfectly around the back of his neck, the way his fingertips incited goose bumps wherever they traced, the way they moved so fluidly to the bed, never breaking their kiss. Getting lost.

III

Margaux woke to the sound of birds chirping outside the window. She walked through to check on Vaughan – still sleeping. When she returned to the bedroom, Sherlock was sitting on the edge of the bed. His shirt was unbuttoned and his hair was messy, falling into his eyes as he bent over to put on his shoes. She pulled her robe tightly around her waist and sat in a chair opposite him.

"I have to go. There's a case I need to start preparing for," he said.

"No rest for the wicked," she replied.

He stood up and buttoned his trousers. Her eyes trailed the sliver of bare torso between his open shirt. She bit her lip absentmindedly.

"Compose yourself, Margaux," he said.

She blinked and shook her head, realising she'd been staring. "Sorry," she said with a smirk.

Sherlock grinned as he fastened his buttons, picked up his coat and headed for the door. He stopped and turned as he opened it.

"Oh," he said. "I thought you should know I'm going to make Janine my girlfriend."

Margaux stood up and followed him. "What?"

"There is somebody I need access to. Somebody dangerous. She is a way in."

"So you're just going to use this woman?"

"Yes."

He was so matter-of-fact that it made her laugh.

"Sherlock, do you understand why I'd be upset by that?"

"Yes, but I have to do it."

Margaux sighed. "One step forward and two steps back," she muttered under her breath.

"Hm?"

"Nothing."