"Who are you waiting for?" John Watson asked.

"What makes you think I'm waiting for someone?"

His friend's back was to him, and John smiled to himself.

"Because you've been watching the clock for the past half an hour, thinking that I wouldn't notice."

"Oh, so you have learnt something during our time of working together?" Sherlock replied, throwing one final – almost imperceptible – look towards the street.

"So?"

"If you must know, Molly."

"Molly's coming here? Why?"

"To tell me something."

John frowned. Something was definitely going on, and once again, he felt as though he was several steps behind.

"Don't you want to know what she's going to tell me?" Sherlock asked.

"Well, I was assuming I'll find out when she gets here."

"She's pregnant."

John felt as though somebody had smacked him in the back of the head. He actually dropped his phone, and fumbled on the floor to retrieve it.

"Pregnant? But how do you -? Why would she…?"

He studied his friend's expression, and suddenly there was no need for him to finish his question.

"You and Molly?" he gaped, aware that he was barely able to construct a cohesive sentence. "And you -"

"Yes, John, approximately seven weeks ago – forty-six days ago, if you must know – I had sexual intercourse with Molly Hooper."

As usual, Sherlock seemed incredibly matter-of-fact about what felt to John like a monumental revelation. He hadn't even been sure that his friend had properly made amends with Molly since the devastating interventions of Eurus, but now it seemed things had gone beyond 'amends'.

"Okay. Wow," John said, shaking his head quickly. "Full marks to both of you for keeping that one a secret. But what makes you think that she's pregnant?"

"Well, it was planned."

"You two planned this?"

"No. I did."

"I'm sorry, what? You planned to get Molly pregnant? Excuse me for being an idiot, but why?"

"It's what she wanted. She wants to have a baby."

"She told you that?"

"Not verbally."

"What does that mean?"

"I deduced it, it wasn't difficult."

John felt his stomach lurch, and this time it was Sherlock Holmes who needed to feel the full force of a smack in the head. He was sorely tempted to do it right now, himself. Despite what he had just said, however, his friend looked remarkably calm.

"Please, Sherlock, please don't tell me that you arrived at this conclusion based on…on…some assumptions about Molly's age, or, or how she is with Rosie – because I know she's great with Rosie – or -"

"Oh please, John, I would never permit myself to stoop to the level of tabloid pop-psychology. There were other signs, clear indicators. Trust me."

John rubbed his face with his hands momentarily. Sherlock had put Molly Hooper through the emotional wringer several weeks ago, and now John feared that his friend had landed on the most wrong-headed way of making it up to her.

"Okay," John said, trying to level his voice. "So, what, you two had a one-night stand seven weeks ago?"

"I detest the phrase, but I suppose some would call it that."

"What, just like that?"

"I took her to dinner first," Sherlock replied, almost sounding offended.

"And then…"

"Then, yes, there was the sex."

John almost found himself smirking at the way his friend said this.

"But hang on, how can you be sure that Molly's pregnant?"

"Well, we didn't take any precautions."

This in itself surprised John about Molly, but he could well believe that such a presumably unexpected event might have caught her on the back-foot.

"Yes, but still – one time, Sherlock. Of course it does happen, but -"

"She hasn't replied to my texts since last Friday – conclusion: she is avoiding me. She had a doctor's appointment marked in her work calendar two days ago – no need to ask me how I know that, John – and another appointment marked out for today. An appointment with the community midwife, I would strongly assume. That appointment started at 4pm and, given the workload of the average NHS employee, would have been approximately fifteen minutes late and lasted no more than twenty minutes, meaning that she would have made it to the bus stop in time to catch the bus at ten to five, meaning that she will be arrive at 221B Baker Street somewhere between 5.25 and 5.35."

"Okay…" John said again slowly. "I see you've planned all this in your typically sociopathic manner. But still, one time?"

"As I told you, planning. You probably don't want to know the details, John, but it involved tracking cycles, isolating the best window for fertility - and me building up my consumption of zinc, hence all of those steak dinners."

John pulled a face. What woman wouldn't be delighted to know that the man they slept with had been tracking their menstrual cycle? Or that the same man was secretly trying to boost his fertility? And now that Sherlock mentioned it, he did remember a short period when his friend seemed to be eating the same food on hard rotation – but that kind of thing barely raised an eyebrow these days.

"You know this is deeply sociopathic, Sherlock? Not to mention arrogant in the extreme. You can't just assume that a woman wants a baby and then take it upon yourself to make that happen -"

"I didn't assume - were you even listening to me?"

John silenced him with a raised hand to indicate that his friend should shut up, as he was barely getting started.

"Babies are a big decision, Sherlock - they change your life, in case you hadn't noticed. If this is true – and yes, shut up, I know you think it's true - how do you imagine Molly is feeling right now? People think very carefully before bringing a child into the world, people plan these things – admittedly, not always, but Molly is that kind of person. Do you think this is a decision she would have made with all the facts to hand?"

"She'll be an excellent mother," Sherlock put in.

John let out an exasperated sigh.

"That, Sherlock, is not the point. You deceived her. Knowing how Molly Hooper feels about you, you deceived her, made her believe something that wasn't true, just so you could orchestrate something that you somehow believe that she wants."

He saw a wrinkle appear on Sherlock's brow.

"Which part of it wasn't true?"

Now it was John's turn to look confused.

"Oh, so you're saying Molly was aware that this was just a one-night stand?" he asked, deeply unconvinced. "That you were very clear upfront that, yes, you wanted to have sex with her, but no, there wasn't anything more to it than that?"

"If you're asking if we discussed it in depth, then no," Sherlock replied.

"She must be devastated," John said. "Now I'm asking myself how I hadn't noticed. I mean, what's been going on during the past seven weeks, Sherlock? She's been round here every few days, so, what, are you now just acting like that one night didn't happen?"

He saw an expression pass across Sherlock's face, one he didn't recognise. Hang on, was Sherlock Holmes blushing?

John folded his arms, focused his frown on his friend's inscrutable expression.

"Now I think I'm missing something," he said.

"I may have misled you somewhat during the course of this conversation," Sherlock said eventually. "Or, looking at it a different way, you have made assumptions, chosen to adhere to a particular interpretation. The fact is…there were other nights. Actually, technically speaking, not always nights."

John stared at him now, open-mouthed.

"How many nights – or not-nights?"

"Oh for god's sake, John, is that really important?" Sherlock spat. "Several nights, lots of nights…okay, if we really have to put a number on it, twenty-eight nights. Or not-nights."

John felt his eyes spontaneously widen at this confession, and he couldn't help but let out a laugh. And keep laughing.

"Why are you laughing? Is that a lot?"

"I would say it demonstrates a distinct pattern, Sherlock, wouldn't you?" John eventually managed. "If Molly is pregnant -"

"She is."

"If Molly is pregnant," John continued, unabated. "Then it's hardly surprising, given those odds."

Sherlock shook his head resolutely.

"It was that first night. Since then, we've…she's made me…"

"Use protection?"

"Yes," Sherlock replied, looking relieved that his friend saved him the awkwardness. "Precisely."

John sighed. For a highly gifted mind, Sherlock Holmes could be decidedly obtuse.

"But doesn't that tell you something, Sherlock? Namely that Molly has no intention of getting pregnant, of having your child?"

"Wrong. She insisted we take precautions only because that's what she felt she should do, that as a modern, strong, independent women, she felt that's what she had to do. If she didn't, it would look like she wanted to get pregnant, and she'd worry about how that would seem to me, how I would interpret that, what it would mean for what was going on between us."

Arms folded, John glanced at the floor, then back up to meet Sherlock's face.

"And what is going on between you, Sherlock? Because if you're using Molly, you'd bloody well better put an end to it right now. If -"

He stopped mid-sentence, halted by the look on his friend's face – Sherlock Holmes looked burned.

"You've fallen for her," John said quietly, a smile beginning to appear on his face. "For all of that planning you did, you didn't plan for this. I'm right, aren't I?"

"You were there," Sherlock replied, a note of terseness in his voice. "You were there when I told Molly I loved her."

Sherlock was averting his gaze. He was, John realised, for once in his life, out of his depth.

"Yes," John agreed. "I was. But to be honest, Sherlock, I never expected you to act on it. After all, it would have been easy enough to explain away, and you know full well that Molly would have eventually forgiven you."

"Believe me, John, I'm perfectly aware of that," Sherlock replied, a note of exasperation in his voice. "But after all that I put her through, I…I came to the conclusion that if it was within my ability to do so, what I needed was to make Molly happy. Hence the baby."

John sighed in disbelief.

"You know something, Sherlock, you're a bloody idiot. You've got this completely backwards. I have no way of knowing for sure what she thinks about having a baby, but I think I can say with a good degree of confidence is that Molly Hooper is already happy."

The consulting detective looked genuinely perplexed.

"You, Sherlock," John said, taking a step towards his friend. Still, he seemed nonplussed.

"What would make her happy is you," John explained. "And god knows you're a lucky bastard to have found the one woman in the world for whom that's the case."

"Right."

Sherlock's brow was furrowed, his arms folded as he focused his gaze somewhere on the floor.

"I mean, not if you're a complete cock to her, obviously," John added. "I mean, any more than you have been in the past. If you really want to make Molly happy, just make this work, Sherlock – finish what you've started."

Without looking up, Sherlock replied in a low, surprisingly uncertain voice.

"You make it sound easy."

John laughed, leaning back on the windowsill that overlooked the road.

"It isn't easy, Sherlock, it's bloody hard," he replied. "Think of the hardest case you've ever had to crack and then double it. But I know you – five years ago there wouldn't have been a chance in hell, but now…now you can do it, no question. You know why? Because now, you want to."

There was a pause.

"It's five-thirty," Sherlock said.

As if on cue, he heard the doorbell ring downstairs. Molly always rang the doorbell, out of politeness, even though she'd long since had a key.

"What are you going to say?" John asked.

He saw Sherlock blink, trying to focus his thoughts, apparently without much success. John saw him swallow, hard.

"I…" he began, his voice barely more than a whisper. "I don't know."