A little scene that would have taken place between TSoT and HLV. I found really strange really strange how Sherlock disconnected from his friend during HLV, especially when we've seen him relying much more on them during TSoT. To me, the only reason for Sherlock's odd behaviour and relapse in drugs is that he's ashamed of something. Of course, as I ship deeply Sherlolly, I totally dig the idea that somewhere in between the two episodes, Sherlock becomes sexually attracted to Molly and is sufficiently upset by it as to avoid his friends after that - not wanting to be a reason for Molly to question her engagement, nor wanting John to discover that he might harbour some attraction to an engaged woman, which John would morally disapprove. Anyway, it also does explain how he came to use Molly's flat as a bolthole. :)

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When Sherlock arrived at the morgue, he found himself quite displeased at the sight before him. More precisely at the missing person in the sight before him. As a matter of fact, instead of Molly Hooper, only pathologist that he would work with, there was Robinson, who, while somewhat competent in his own right, was no Molly Hooper. Sherlock froze just in front of the door and tried not to roll his eyes at the man's nervous jump. Robinson, recoiled from him like he was a snake and immediately started blabbering:

"Sh-sh-she's not here. She took a-a-a day off."

"She took a day off? But I have a case." The detective replied, genuinely surprised. Now, that was inconvenient. A case had been brought up by Lady Smallwood the day before and he already knew that he would need to put his research elsewhere than Baker Street. Normally, he would have tried to set up everything at John's and Mary's but they were away on their sex holiday. Surely, Molly's flat would be the perfect place. It was comfortable from what he remembered from his time there before leaving England and he wouldn't be inconvenienced as she wasn't that much in there lately – at the last thought, he refused to acknowledge the little sting in his chest. Unfortunately, reality had this pesky thing of getting in the way of the detective's plans lately and there was no Molly present so he couldn't request the use of her flat as bolthole. While he was thinking of the inconvenience of it all, the man kept blabbering and Sherlock muted him in his mind until some sort of mumbling caught his attention as he was turning to leave the morgue:

"Wedding gown try-ons, you know she's getting married, right? She's probably at that wedding shop with her best friend and mother…"

At that Sherlock, perked up. While it was a delay in his schedule about the case, it might be fun to go and hunt down the petite pathologist. He grinned and started to make a list of all wedding dresses shops there were in the budget range of Molly. If he knew her well enough, and who was he kidding, of course he did, he was sure he could narrow down the search to three possible shops. He left Bart's without even addressing Robinson, sure that in a matter of hours, he would have found his pathologist and be in possession of a new bolthole.

As a matter of fact, it was on his fourth trial that he found which shop Molly Hooper was in. He was a little disgruntled at the little error in his calculation, but of course, there was always something, wasn't it? He slipped inside the shop through a window and managed to stealthily move around the shop until he heard the voice of Molly discussing with her mother and friend. The friend's speech pattern was a little slurred and the interest of Molly's mother caught by something else. Sherlock grinned as he saw the perfect opportunity to get on a little chat with his pathologist. Without thinking further, he slipped himself in the dressing room and found himself at the back of the pathologist. What he foolishly hadn't anticipated was that his pathologist would not be dressed. As a matter of fact, Molly was clad in nothing else than a little white lace and silk bustier with matching knickers. Her hair was atop of her head in the prim little bun she'd donned for John's wedding. She also had old fashioned sheer seamed stockings. They were kept in place by suspenders, the long seam at the back tracing the curve of her legs, matching the blue soles of her nude high heels. The entire impression was not unpleasant to the eye but was quite the change from her normal attire. And if he felt a little lightheaded, Sherlock attributed the sensation to a probable lack of sustenance, ignoring the fact that he had tea with biscuits two hours ago. Anyway, before he could give more attention at the sensation, he saw Molly turn and a look of surprise etching a little o on her small but well defined lips.

"Sherlock?!" exclaimed Molly in a low voice as she turned and saw the detective perusing her with a strange look on his face.

Before making any more noise, she turned back to check and see if Meena or her mother had noticed the man slipping inside the dressing room.

"Your friend is lethargic from the cheap Champaign she's obviously largely indulged in and your mother is too taken up in the wedding magazines too notice anything. You're quite safe." Murmured a low voice in her ear.

At that she turned once more and almost collided with the detective. She almost started shrieking again, when she finally remembered something. She was currently in her wedding undergarments: white lace corset and knickers as well as stockings for good effects. And her beautiful new nude high heels – precious things that had been made especially for her wedding day so as to be both comfortable and bring her to a size where Tom would be able to kiss her without wringing his neck.

"Damn it, Sherlock! You shouldn't be here!" she hissed angrily, trying to keep her voice low so nobody would hear whatever was going on behind the heavy curtains of the dressing room. She also started covering herself before going back to gesturing again as she saw there was no way for her to hide anything with her bare hands.

"Molly, the Woman tried and failed to fluster me by welcoming me naked in her house and I went to Buckingham Palace in nothing else than a sheet. Surely, you understand that I don't care for all this." Replied evenly Sherlock, gesturing at the clothes or lack of thereof.

Molly eyed him suspiciously, feeling that there was something a little too even in his voice. As if Sherlock had already examined and repeated what would be the best thing to tell her. Just like when he used to manipulate her. But truly, after a few long seconds, she couldn't pinpoint what would exactly be the point for him to catch her in her knickers and corset, so there had to be another thing he wanted from her.

"What do you want Sherlock?" this time, her tone of voice was less outraged but still quite annoyed.

Sherlock, keeping his face schooled in blank expression and making sure his eyes never left her face, suddenly relaxed as he saw that he'd managed to pass this round. At the shrewd narrowing of her eyes, he stilled once again, not wanting her to feel as if he might have taken a good look – which he definitely had and maybe the tiniest bit not just by habit. But he also knew that his pathologist would not take kindly to his curiosity regarding her measurements. Anyway, better to focus on the reason why he was there rather than adding fire to the fight brewing regarding her current clothing.

"I have a case and I need your flat as a bolthole." He quickly summarised.

"Why don't you use your other boltholes?" replied quick-to-the-point Molly, with the same inquiring expression she had when he came to her for computing the amount of alcohol for the stag night. As he thought of that, he remembered that she had exactly the same bun, if not the same clothes. But thinking about her face when she had said she were having "quite a lot of sex" or even her confident mastering of the whole conversation and adding this to her current attire was definitely not the way for this thought process to go. So, trying to divert his mind from digressing further, he rushed:

"I need somewhere private with at least a minimum security. Thanks to the additions done during the last two years, your place is perfect regarding what I need. Moreover, you won't be much there."

"Are you saying that I'm an inconvenience in my own flat?" said Molly starting to feel a little slighted.

"No, no. I mean. It obviously won't be a problem for you as you're currently spending a lot of time at Tim's… I mean Tom's." having a lot of sex, he didn't finish. Again, with the little quote. Why this stuck to his mind, he really didn't know. To try and calm down his unruly mind, Sherlock sat on a chair opposite Molly in the corner of the little cabin.

Molly on the other hand, didn't know how to react. Sherlock seemed fidgety, which was to be expected when he was on a case. Yet, this time, she couldn't help but feel there was something else to the manic energy of the detective than just the high of the chase. She couldn't put her finger on it but she was sure there was something else. She looked at his face, trying to decipher his falsely tranquil expression. Nothing. She finally sighed:

"Fine, I'll give you a spare key to my flat. But, I want it back when the case is over, right?" she said, turning and bending to retrieve said key in her bag.

Sherlock blessed his excellent self-control as Molly made for her bag. She seemed to have readily accepted that he hadn't peaked a little at her and had even quite promptly agreed to his suggestion, all of this without him uttering anything that might be construed as not good. So, for once, Sherlock felt as if he'd had complete control over the situation, which curiously enough wasn't that frequent when dealing with his pathologist. Until, of course, the sweet, little pathologist, so innocently bent to retrieve the spare key in her bag. The fact was, the sight that Molly presented was anything but forgettable. Bent at the waist, her hands rummaging in her bag, her bottom deliciously thrust high in the hair. And most of all, her long, magnificently shaped legs, their curves definitely enhanced by the not-so-demure stilettos. With that beautiful blue line tracing the back all up to her thigh, just before giving way to creamy soft flesh. At that, he felt hot. As some images started crashing together in his mind, images he would never before have associated with Molly Hooper, Sherlock felt as if the world had shifted on its axis. The small little room in his mind palace that had before only contained images of the Woman – remembered or imagined – burst open with a gush of wind and new images started filling in. Molly, naked on a bed with just a sheet covering her while she slept with abandon after having been thoroughly shagged, Molly clad in only her lab coat and sitting on a stool with her legs crossed, Molly's hair gripped tight in his hand as he kissed her. When his overactive mind finally started to draw out fantasies about what he could do with his pathologist in this very cabin – him crowding her until she had her back to his front, letting his Belstaff bracket both of them while he kept her head angled so her eyes were fixed on them in the mirror, his hand moving aside her knickers until he could play her like a cherished instrument - he knew he had to do something to jolt his mind out of this. His eyes still locked on the blue seam of her stocking – he seemed utterly unable to detach his gaze for some reason, Sherlock started thinking about the tensile strength of the fabric, going back to his mind palace for his research on the subject. As he was feverishly going through all possibilities, he faced himself faced with a problem: was it nylon? Or silk? Or another fabric entirely? Too many variables. He had to, no, needed, to narrow it down.

Molly was still rummaging inside her messenger bag – sometimes, she cursed herself to have so many things in it as it took ages to find anything – when she felt something at the back of her leg. She gasped and turned her head and saw Sherlock bent toward her, his eyes focused on the line where his elegant fingers pressed. She froze. The look on Sherlock's face was undecipherable but intense. In the next moment, she was jolted back to present when the fingers started a caress, following the thin line drawn by her stockings. Yet, unable to move, she could only whisper:

"Sherlock?"

This seemed to get him back to Earth instantly and he obviously shook himself. He retreated back to the chair, as if nothing untoward had happened. Finally, his eyes, once more shuttered, left the back of her thighs and came to her face. And the detective said one thing she would have never expected him to say:

"The seam is blue. It's uncommon. And it matches the sole of your shoes."

She couldn't help but laugh a little at that. "Oh, just you know, for the wedding. Something new, something borrowed, something blue…" Her voice trailed down as she finally caught up with the one thing that shouldn't have left her mind at any time and most of all when she was trying on bridal gowns. Her wedding. And while reality came crashing down around both of them – Sherlock freezing also a little at her words, they heard a clear voice asking from behind the curtains.

"Hello Miss, the dress you requested is finally available. Sorry for the wait, I can come on in and show it to you, if you want."

Sherlock made to move, but Molly was quicker and stilled him with one hand at his shoulder and the other pressing a dainty finger to his mouth. As their eyes met and held, she found herself answering in a clear, confident voice:

"Just a minute, I'm almost finished getting the corset clothed. Can you put her on the suspender? I'll retrieve it once I'm done."

Still frozen to their places, they heard a reassuring line about hanging the dress next to the cabin and then footsteps left. Molly finally took back her hands to herself, feeling them tingling from where they'd been in contact with Sherlock. The sensation was at the same time extremely sensual and gut-wrenching. If Tom knew about this, he would be hurt and betrayed. It cut at her. Because she did love him. Yes, worst irony of all this was that despite what people might think she really was in love with Tom, kind, awkward and average intelligent Tom. But she also loved the brilliant man in front of her. The man that scrutinized her face with an intensity that usually was only reserved for cases. She sighed and he recoiled visibly. But before, he could escape, she stopped him and pressed something into his hand.

Sherlock left then, or more accurately fled the tiny woman that wreaked havoc in his mind palace. All these images, that sudden desire was unexpected for him. Lust he knew. But never before had he experienced it for someone he was really fond of. The feeling was new and exhilarating. The fantasies weaving in his mind not only of sex and games but also of comfort, tenderness. He still felt her finger on his mouth. Yes, the playfulness had been there he remembered as heat started coursing in his veins. But his mind proceeded to show him the flash of pain in her eyes as she thought about her fiancé – the quick touch to her engagement finger, the unmistakable clue. Cold dashed everything inside him. He couldn't do it. Couldn't pursue this when she loved another man, even if she might still have that little crush on him. Lusting openly after her when she was in love with another would destroy her. Even if she'd never be at fault, her loyalty was too big for her to feel otherwise than a traitor. He thought back at the discussion he'd had with Mary's usher. Yes, that was that. At the same problem, he'd have to apply the same solution. To distance himself from her – all this because, just as he'd had with the usher, he knew that he would never be able to think about Molly in a platonic way ever again. She had stormed his mind palace and evicted the Woman from his fantasies. Not a small feat indeed.

As he finally came to terms with what should be done regarding Molly Hooper, Sherlock thought back to the case. Magnusson. Such evil. His hands curled on themselves at the disgust he felt toward the man. And finally the weight in his hand registered. He stopped from his brisk pace and opened his fist. In his hand, there was a small little key. The key to her place. His bolthole.

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Yes, my take on Molly's engagement is that she really was in love with him. Obviously she was still in love with Sherlock also but I do think that you can love two people at once and not for the same reasons. So, little angsty ending on both sides that would explain why the weird interactions between Molly and Sherlock during the drug test (am I the only one to feel that there is much more subtext between the two of them than just anger at a drug relapse?).