Disclaimer: I do not own Sherlock.

Warning: Established Adlock.

1 month before the Wedding...

"Sherlock, I need your help." Sherlock looked up, frowning at John. It wasn't often that John asked him for help, especially when he was in the middle of an experiment. Well, except for the time he had asked Sherlock to be his Best Man. The wedding was in a month. What did he need now? He was currently holding a pair of tongs which held a pancreas on the end. He was holding a fire in his other hand, using the very simple trick of 'lighting' your hand on fire.

"John, I'm in the middle of an experiment. An important one at that."

John shifted nervously. "Um, yeah, I really need help."

Sherlock frowned, shook his hand letting the fire go out, putting the pancreas onto the plate in front of him, and examined John, deductions already forming in his head. Nervous about something. Needs help most probably with the wedding. Mary takes care of most of that. Embarrassed, but not clothes. We decided that just yesterday. Hoping I know it, from expression. What do I know that John won't know that he'll need for the wedd-ah. Dancing. "You need to learn how to dance."

John's head shot up. "What-how-yeah." He finished, looking sheepish. "And-"

"And you are asking me because you presume I know how to dance because of your guess on my background."

The doctor winced again, but nodded. "Do you?"

Sherlock sighed, knowing that he couldn't refuse his friend. "Yes." He sighed, removing his goggles. "A waltz, yes. Others, not so much."

John, from where he had been staring at his feet, looked up eagerly. "Yeah, that's fine!"

Another sigh from the Consulting Detective as he looked at John. "Fine." He stood up, removed his gloves, set them on the table, and then walked over to his laptop, where he typed in something that John couldn't see.

"Um, what are you doing?"

Sherlock looked up at him. "Emailing Lestrade to tell him that I'm on a break from the case now."

"Then why don't you text?" John gestured to Sherlock's phone, but Sherlock didn't even look at it.

"He lost his phone. Needs to get a new one." He scowled. "For a man who is organised, he needs to make a space in his timetable to get his phone! I can't always rely on emails."

John nodded slowly, used to his friend's eccentrics. "Ok…" He then walked over to the curtains. "Should we, um, close them?"

"Why?" Sherlock demanded, looking up from his laptop. Embarrassed at asking, embarrassed if people catch him, only logical thought. Doesn't want to be thought of as a couple. He sighed irritably as he seemed to notice something from John's expression and waved his hand. "Go ahead." John sighed with relief.

Before long, Sherlock had one hand holding John's hand, and the other on his shoulder. He was directing John about his stance. "Not so rigid, but not too relaxed either. Grip firmly," He winced as John's hand nearly clamped down immediately on his waist. "Not that hard." John cringed, and relaxed his grip. "Not so low." He gestured to John's left hand.

"In dancing, you have to keep the rhythm. If you know the rhythm, you'll be fine in any song."

John nodded, and Sherlock could see him trying to memorise all the data. "Ok…"

"Basically, the most important move is moving around. Feet. Twirls and all the others come in after you learn the basics." John nodded once again. "For most, there are usually 4 steps for the most basic. One, two, three, four." He led John on the steps, wincing only slightly as John stepped on his toes rather painfully.

John cringed again. "Sorry." Then, he seemed to remember something. "Don't tell Mary?"

Sherlock sighed, but nodded his consent. This was going to be a long month.

A day later...

A knock on the door. Sherlock didn't even look up from his microscope as he replaced the slide. "Come in!" Can't be John. He's got work at the surgery today. Mrs. Hudson is out grocery shopping. Lestrade doesn't knock. Neither does Mycroft. Mary.

His trail of deductions ended with the answer even as she stepped in. "Mary. What do you want?"

Mary was fidgeting only slightly. "I need your help."

Behaviour suspiciously like John's when he asked-God, not her too?!

Sherlock looked at John's fiancée. "Dancing?" Mary nodded, not surprised at his rapid guess. No, not guess. Sherlock Holmes didn't 'guess'. Sherlock raised an eyebrow. "You don't know how to dance?"

Mary bit her lip. "Yeah, and-"

"You're hoping that I can help you because John knows how to dance." Sherlock finished. He was about to say John had asked him about the same thing, but remembered his promise. He smirked slightly. How ironic.

Mary nodded. "And don't tell John?"

Sherlock sighed as he had did on John's first lesson. "Do we have to close the curtains?" Mary looked surprised at this comment, but nodded, already halfway across the room to close the curtains.

Remembering his words from John, but now applying it differently, he then took the position with her. "First thing. Not too tight, but firm. Try not to step on toes. Please." Mary giggled at his face. "Rhythm is important. If you have the rhythm, you'll be able to dance to any song. First, you have to learn the basics, but one thing you must have is balance, if John tries anything else with you."

And he will. Sherlock smirked, wondering what they will think when they found out that their counterpart were also taking lessons from Sherlock, of all people.

Mary nodded slowly. Sherlock tried not to chuckle at her face, remembering the same expression on John's as he continued to lead her on.

1 week before the Wedding...

Sherlock was tired. It had been 3 weeks since his 'secret' dance sessions with John and Mary had started, and he was now wondering how Irene managed to have the relationship with the prominent novelist and his wife. He felt like her, keeping a secret on both ends, when both were in on a relationship.

At least he wasn't going to ruin their wedding.

He smirked at that, briefly wondering where Irene was, before looking up as Mary came in, for her lesson after the morning one had been interrupted. This morning had been a particularly close shave.

Both had come at the same time, Mary early and John late for their sessions. Sherlock, through means of quick thinking, had covered for both, and had managed to block out any suspicion, helping both sides separately. John dragged Sherlock into the kitchen, reminded him not to tell Mary, and stayed there looking for tea. Mary dragged him out to the stairs, and again told him the importance of not telling John.

Sherlock, amused, had agreed and walked back to the living room, giving a smile to both sides, with both sides oblivious to the parter next to them, and smiling at him as well. They had all ended up looking through the guest list again, double checking the places where the guests would sit.

The music blasting from the speakers was no longer disco, but was now a simple waltz. Sherlock smirked to see how many people were trying to look dignified and perform complicated moves. He turned to leave, but a hand, with red manicured nails, landed on his shoulder, and he turned, a small smirk on his face. "Ms. Adler."

"Mr. Holmes." She purred. "Leaving a wedding early, are we?"

His smirk grew. "May I have this dance?"

"My pleasure." Irene's eyes held amusement as she accepted Sherlock's hand. "Seems like you have been busy in this section of the wedding."

Sherlock was not surprised how she knew. She was one of the smartest people he knew, besides Moriarty or Mycroft. She had her ways of finding out things. "It was tedious. Both ends."

Irene smirked as he dipped her down to the floor. "I presume so. Mary seems fine, isn't she?" Sherlock smirked in return, before a thought came into mind.

"You're not safe in England."

"You just remembered that?" The former Dominatrix smiled. "Don't worry, Sherlock." She purred. "Just focus on right now, darling." Her face turned troubled. "There's something I need to talk to you about."

John looked up from where he had been dancing with Mary. Everyone were making fools of themselves…well, not exactly fools, but slight show-offs as they tried to outdo each other in this simple dance.

Thankful of Sherlock's lessons, John applied the skills that he had learnt during then now, and Mary danced expertly with him.

However, he soon noticed everyone's attention on a dancing couple who seemed not to know of anyone else. Sherlock and…Irene Adler?! His mind screamed at him to try and solve how she was still alive, but there was no doubt about it. Sherlock. He had to have a few words with his best friend after this. But for now, he gaped at them with Mary, who seemed pleased that Sherlock had a dancing partner.

Their movements were simple, but elegant, and graceful as they moved fluidly. Both were, in their own way, attractive, and a matching set with their high cheekbones, blue eyes, and dark hair. Both had that aristocratic aura around them that just demanded their attention. Irene's hair cascaded down her back, her dress red and backless as both seemed to be engaged in silent conversation, though still dancing. "Who's she?" Mary whispered.

John frowned, noticing Sherlock's brief alarmed expression before he schooled it back to his normal expression. "Later."

They didn't seem to notice anyone around them as they continued dancing, before the song soon slowed to a stop. By now, everyone was around in a small crowd, watching the two dance with grace. When it ended, Sherlock dipped Irene down so that her hair nearly touched the ground. Both were smirking at one another, as if in the middle of an interesting conversation.

Everyone applauded, and John found himself joining in.

Both stood up, straightening up, and the music changed again, allowing the couple to escape any sort of questions. Sherlock and Irene, who John had lost in the crowd earlier on, soon joined Mary and John.

Irene eyed Mary. "Congratulations, Mrs. Watson." Mary smiled at that. The (The) woman's (Woman's) words were genuine, she could tell from years with Sherlock. "It seems like the dancing lessons did you both some good."

Sherlock chuckled as the newly wed couple looked at one another in surprise, gaping, before finally breaking down in laughter, with John looking at Sherlock, "Honestly, Sherlock. You can't keep a secret even if you tried", while Mary was too amused at the irony to care, laughing even as Sherlock introduced Irene Adler! to her. The Woman. The one he had told her briefly about, when she had asked if Sherlock had had any relationships.

"You bloody-"

Irene interrupted to reprimand John, a predator smirk on her lips. "Don't swear on your wedding day, Dr. Watson." She turned to Mary. "Congratulations again on the child." Mary smiled broadly now, ready to speak, but Irene continued. "That makes both of us, no?" She placed a hand on her stomach, which John now noticed was slightly swollen. The dress hide it, looser than the dresses she would have worn if she weren't pregnant.

John and Mary's eyes widened as they stared at Sherlock, who remained unperturbed, raising an eyebrow at the speechless couple.

Mary was the first to react. "Congratulations yourself! Both of you! How long?" She grinned.

Irene smiled gently. "3 months. I hope you are pleased?" All three then turned to John, as if waiting for his reaction. But John was speechless. He couldn't think of anything to say. Irene Adler and Sherlock Holmes were going to have a child. What a disaster and miracle the child would be. Instantly, thoughts flitted into his head before he could stop them.

Irene and Sherlock are in a relationship.

As in hugging, kissing, sleeping in bed-Oh God.

Finally, he regained his speech. "Sherlock." He choked out.

Sherlock smirked. "In case you're wondering, that's Irene asking if you two would like to be the godparents."

AN: Hope you liked…my first (well, second, but the first was a crossover) attempt at a Sherlock fanfic. I was toying with the idea if what if not only John had been the one to ask for lessons. Oh, and Sherlock didn't reveal anything when John and Mary went to dance, so Mary still didn't know that Sherlock had taught John. Review, please!