A/N: I got the idea for this fic about a year ago and I can't even remember what sparked it. Anyway, I've finally gotten around to writing it out, to here it is. I should warn you that there's going to be some vulgar language in here.

Chapter 1: Home Again

Fifteen years. Fifteen years since Sherlock Holmes had murdered Charles Augustus Magnussen. Fifteen years since Sherlock Holmes had disappeared from the face of the Earth. And now he was back.

He knew he couldn't just drop in like everything would be the same. Not this time. There was no doubt in his mind that things would have changed drastically over the years and that he would not be able to have everything back the way it had been. Still, he yearned to see all of his loved ones again, to sit in his chair at 221B and pluck at the strings of his violin. Taking up his old career was out of the question. He couldn't be the famous detective anymore. At the very least, not until he'd found a way to introduce himself back into the lives of those he loved.

He began by visiting Baker Street. It was somewhat early morning then and he was surprised to see that there were lights on and people inside the flat. When he got closer, he realized that it was Molly Hooper and some man he had never seen before. Molly smiled and would have looked as if she hadn't aged a day if not for the hints of grey in her hair. The bottom of Sherlock's stomach dropped out when Molly kissed the unfamiliar man. He wished he could see her left hand to determine the extent of that relationship. He stopped himself there. Molly was happy and he had no right to interfere. Whatever they had been fifteen years ago, it didn't trump this, even if she lived in his old flat.

Molly and the man (brunet, strong features, well paid- most likely a doctor) suddenly turned to look at what was obviously a third person. Mrs. Hudson? No, Molly would never look at Mrs. Hudson with such a disapproving glare. The man was frowning too, but he seemed more shocked than put out. This confused Sherlock. He had no idea who the third person was. He got his answer a moment later when a teenaged girl with long, dark waves flowing down her back came out the front door. Her body language made it extremely clear that she was not happy. She wore a uniform for the local school and carried a black messenger bag decorated by three button pins, but Sherlock could not see what was on them from where he stood. Her face was unmistakably shaped like Molly's, as were her eyes, although they were clearly a vibrant green, rather than brown.

Glancing on last time at the windows of 221B to see the pathologist and her beau watching the teenager walk away, Sherlock made the decision to follow her. The least he could do for Molly right now was make sure that her daughter made it to school safely.

"Good afternoon, Lilian," Cypress Hooper greeted her best friend morosely as she slid into her seat at the back of the chemistry classroom.

"Your mum still determined to ask Matt to marry her?" the blonde inquired sympathetically and Cypress nodded.

"All I can do is stall her by interrupting their little moments." She spat out the last word like it was some form of revolting fungus and punctuated it all by slamming her Chemistry textbook down onto the table. Lilian was startled to the point where she nearly jumped off of her stool.

"Really, Cy, was that necessary? Why are you so against it anyway? Matt makes your mum happy and he's never been anything but charming." At this, Cypress fixed her friend with a chilling emerald glare.

"I've told you before. It wouldn't be right."

"Cy, you're dad's-"

"Dead. I know." Cypress' tone in that pithy remark ended the conversation and made Lilian look away to focus on her work.

Since the 'sudden and unexpected' resignation of their chemistry teacher a week ago (which half the school knew to be in some way Cypress Hooper's fault, although they didn't know about the illicit activity she'd caught him engaging in), the deputy headmaster had instructed them to do the work from the book until a replacement was found. Cypress had just been about to copy out the first problem for the day when an unknown man walked into the classroom, commanding the immediate attention of all of the students.

"Are you the new teacher?" someone blurted out.

"Yes. My name is Alastair Williams," he replied in a velvety rumble of a voice. He was middle aged, thin, and wore thickly rimmed spectacles over his almond shaped brown eyes. Time had been exceptionally merciful to his angular face and his hairline. His short, dusty auburn hair hadn't a speck of grey in it, but Cypress strongly suspected it was dyed. He was obviously one of those people who aged gracefully and there was something familiar about him that made Cypress pay attention.

Mr. Williams began roll call without any further comment and sped through until he got to Hooper, Cypress. He paused for a brief moment as she raised her hand, his eyebrows forming the quickest of frowns before he moved on. The corners of his cupid's bow lips twitched upwards when he reached the end at Watson, Lilian, as if he recognized the name. He didn't dwell on it and moved right into setting his rules.

"There will be absolutely no speaking out of turn or messing about in my class and don't ever think you can get away with anything in here. I will see. For example, I suggest that Mr. MacFinn take his hand out of his trouser pocket and wait to text his friend after class." An incredulous and embarrassed James MacFinn instantly drew his hand from his pocket, his phone falling out with it, causing several of his classmates to laugh. "Now, put your books away and copy down what I am about to write on the board." Mr. Williams proceeded to write out a series of instructions for what was obviously an experiment. The rest of the period proved to be far more interesting than anything they'd done in months. They actually got to use fire for once. Ryan Farthing got his finger burnt, but only because he hadn't been paying attention.

Mr. Williams was admittedly rather harsh in his scrutiny of his students, but he never said anything that was unfair or untrue. He seemed to pay particular attention to Cypress and Lilian's work, but they did their best to ensure that they didn't give him a reason to call them out. Cypress enjoyed the snarky replies he made to students muttering about him under their breath. If things continued on this course, Mr. Williams might very well become her favourite teacher. Mind you, that was quite a compliment considering most would find it hard to beat the razor sharp wit of Ms. Sheffield, the literature instructor who had a strange obsession with a fantasy septology from the 2000's.

After class, Cypress stayed behind to ask the new instructor about something important which would determine whether she would like him or not.

"Excuse me, sir," she began, cautiously approaching him. He did not look at her as he answered.

"Yes, Ms. Hooper?"

"I, er, I usually stay for about an hour after school to, ehm, do experiments. It's been made clear that I am not to do this without supervision, so, er, do you think-" Cypress had never been good at making requests of people. Hell, there weren't many people she could easily talk to about anything. Someone had even once told her that she was a walking social disaster.

"Yes," Mr. Williams responded without letting her struggle to finish. There was something natural and comforting about the way he seemed to instantly understand her. Oh yes, he was her new favourite teacher. She grinned broadly and thanked him before practically skipping out of the classroom. Things were looking up. She didn't let the grousing of her maths teacher get her down and it didn't seem long before she was back in the lab, setting up her first independent experiment in weeks. She smiled to herself at the comfort of hobby, one which her mum had encouraged her to pursue from a young age. Getting back to it was like stepping into a warm bath.

Mr. Williams appeared just as she was checking to make sure that the fume hood was working properly. He watched her silently with a passive expression as she went about her business and she couldn't help but wonder what he was thinking. All of that was forgotten when she reached into the glassware drawer at her table and felt a sharp pain on the pad of her thumb. She let out a small gasp and withdrew her hand to find it bleeding rather profusely.

"Mr. Williams..." she called after biting back a whimper. He strode over to her, looking slightly alarmed at her wound. Cradling her hand in his own, he examined the damage.

"It's long, but not deep enough to need stitches. Stay here," Mr. Williams stated before disappearing into the supply room for a minute. He returned holding a box of cotton balls and a bottle of hydrogen peroxide. Cypress' eyes widened when she realized what he was intending to do.

"Shouldn't I go to the nurse?" she asked, not sure how she felt about some teacher she barely knew fixing her hand.

"The nurse is incompetent. He would most likely stick a plaster on this and send you away," Mr. Williams replied bluntly and Cypress giggled.

"Yeah, you're probably right." The school nurse seemed to go about his job with the idea that a plaster could magically solve almost any problem a student might face. Cypress put it down to laziness, rather than lack of medical knowledge.

"Hold still," Mr. Williams commanded, cradling her hand again. She grimaced when he began to clean her cut. It stung terribly, but she didn't want to embarrass herself by making any noise. When he was done, he covered the cut with a few more cotton balls and used medical tape to secure them.

"How is it that you just happen to have medical tape in your pocket?" Cypress questioned, narrowing her eyes at her new chemistry teacher.

"Over the years, I've found that keeping a roll of it on hand is a good idea." Well, that wasn't at all cryptic and vaguely worrying. "There. Now never reach into a lab drawer without looking again." There was a stern, paternal nature to those words that took Cypress off guard. Normally, she would have minded. She didn't like people trying to be a father figure to her, but there was something different about it this time.

"Noted."

"And if your parents ask, you did go to the school nurse. I'd rather not get any 'concerned' phone calls."

"Oh, er, parent actually."

"Apologies." There was a peculiar uncomfortableness in that answer that did nothing to quiet the odd feeling forming in Cypress' stomach.

"It's fine. My mum worries, but I don't think she'll get overly worked up about this." Mr. Williams gave her a tight smile and bade her continue her previous activities.

The tube ride home was a mercifully quiet one. The lack of creepy old men trying to talk to Cypress gave her space to think. She idly traced her fingers over the medical tap on her left hand, pondering her mother's relationship with Matt and the things Mr. Williams had said to her that afternoon.

Cypress could see in her mother's actions that she was trying too hard with Matt. It was like she was desperately trying to achieve some idea about what her life should be like, even though Matt really wasn't able to do that for her. Matt tried to be Cypress' dad all the time, but he had a very poor sense of the girl's needs and sometimes got angry with her for being "difficult to understand". It was especially frustrating because he had never made any real effort to understand her. On top of that, Cypress knew that her mum still had really strong feelings for her dead father and it just seemed wrong for her to force herself to this thing with Matt.

Cypress hadn't known Mr. Williams for more than a few hours, but she already felt safer and more comfortable around him than she ever had with Matt. She didn't understand why. That's just how it was.

She didn't really want to go home, but she stepped out at her stop and walked to 221 Baker Street, her hands in her trouser pockets. Matt opened the door just as she was getting out her key and he smiled down at her so cheerfully that it made her want to roll her eyes. He was obviously trying to show her that he wasn't still upset by her little outburst before school the other day.

"Come on in, Cy. I hope your in the mood for lasagne, because I'm making it for dinner." That's right. It was Matt's day off, which meant he cooked dinner. Tonight, he seemed to have forgotten that she, as a vegetarian, hated his lasagne. This was in addition to the fact that he never remembered that she didn't like him calling her Cy. She only let the people she was closest to call her that. At this point, however, she had utterly given up on reminding him.

"Yeah, sure," she replied automatically as she came inside. She moved past the man she was afraid would be her future stepfather without giving him so much as a glance and ascended the stairs, two at a time, going straight up to her bedroom. Inside, she dropped her school bag near the base of her wardrobe and tossed her tie at her desk chair before collapsing face down on her bed. The duvet was freshly laundered, bless Mrs. Hudson. The landlady was a bit like a fairy godmother to Cypress, doing little things all the time that made her life just a tad better when everything seemed to have gone to shit.

With a groan of exhaustion, Cypress reached out and retrieved her laptop from her bedside table. There were a few emails in her inbox. One was a reply from her uncle about some colleges she was considering. He had found two of them up to snuff after investigating them himself. Another was from Lilian and it was a link to a video someone had taken of Mr. Williams teaching a class of year 10 students about combustion reactions. The was a sudden, startlingly large burst of flame and kids could be heard screaming while Mr. Williams kept a poker face the entire time, like he did this everyday. The video was titled "Badass Chem Teacher" and Cypress grinned, struggling to hold what would surely be a very loud laugh.

There came a knock on her bedroom door and Cypress' smile fell. What could Matt possibly want? She shut her laptop in annoyance.

"Yeah?" The question was laced with thinly veiled attitude.

"Can I talk to you, sweetheart?" It was her mum. When did her mum get home? She must have been too wrapped up in her own thoughts to register the sound of her entering the flat.

"Yeah." Her mum came in, wearing her usual soft smile and bearing a plate with a sandwich and apple slices on it, which she handed to her as she came to sit on the edge of the bed.

"I'm sorry Matt forgot you're vegetarian again. He just needs some time to adjust to those little details of our lives," Molly apologized.

"He's been living here three months, mum. He's not trying," Cypress grumbled before taking a bite of apple.

"Matt cares about you, Cy. I'm sure he's just not very good at remembering things like this," Molly assured her, placing a hand on her shoulder, but Cypress wasn't convinced.

"I don't think so. You told him not to call you 'my Molly' once and he's never done it again, but he won't stop calling me Cy," the teen argued irritably and her mother sighed heavily.

"I'll talk to him, but in the meantime, you really must try to be more civil to him."

"Whatever."

"Cypress." There was the familiar maternal warning tone.

"Sorry, yes," Cypress corrected and Molly rubbed her shoulder affectionately before getting up. She then caught sight of her daughter's bandaged left hand.

"What's that?"

"Accidentally got cut by a chipped bit of glass, but it's taken care of," Cypress explained casually.

"Let me have a look at it later, alright?"

"Okay, mum." That was the unofficially established code between them for "Time to go now, mum." Molly gave her another smile and left her to eat her meal in peace.

Cypress Hooper. That was the child's name. Cypress- a tree symbolizing sacrifice and mourning. The significance of that was not lost on Sherlock Holmes. He knew Molly was the sort to give her child a very sentimental name, so what sacrifice was she mourning? Cypress had said that she'd never known her father. He'd done the calculations and he knew that there was only one possible answer: Cypress was his child. That realization had hit him like a sack of bricks. Good lord, he was a father, an unsuspecting one with real responsibilities to this child which had gone unsatisfied for fifteen years. When he was young, he would have panicked at the thought, but fifteen years of hell had altered his temperament. It didn't matter if he was prepared or not for this responsibility. It was already there waiting for him and he was going to fulfill it. Clearly he couldn't be her father, not truly, not with the way things were with her mother, so he would be her teacher. He would watch over her and make sure that her future stayed bright.

Looking back on it, he supposed it should have been obvious that she was his when he'd first seen her. The girl had bits of him in her features, like her thick eyebrows and sharp profile. His genes had mixed with Molly's to create their child's brilliant green eyes and the chestnut waves of her hair. As far as her personality was concerned, that had yet to be fully determined, but so far it seemed that she had the qualities of intelligence, independence, and strength of will that he and Molly shared. She also had a strong friendship with the Watsons' daughter, a girl who had never known him despite his oath to always be there for her.

Now he could watch over both girls...and grade their homework, a task he found extremely tedious but which he endured for their sake. He didn't know if he'd ever be ready to reveal himself to his loved ones, but he was ready to be there for their children, because they were all that he had.

A/N: So, what's the verdict? Worth continuing? I hope this was at least halfway decent. Thanks for reading.