A/N: Thank you for reading thus far into the story! Sorry for the delay in posting this. I've been really busy with school lately, so it might be a while until the next chapter goes up as well.

Oh, and congratulations to the guest reviewer who picked up on the changed style of writing last chapter.

Sherlock, John and Harry stood for a few moments in stunned silence. Sherlock and Harry stared at John, who was looking at the piece of paper in his hand as if willing it to change.

Eventually, Sherlock spoke. "We should probably get out of the street," he said slowly.

John blinked and shook his head, glancing around, seeming to realise where he was. "Yeah, we should," he agreed, and the three hurried to the side of the road.

"We should try to find Baker Street," Harry said. "I don't know London nearly as well as you two."

Sherlock looked around. "We're on the Marylebone Road," he decided. "That's Regent's Park over there."

"So if we go back this way," John said, "we should intersect with Baker Street." He pointed in the direction from whence they had come.

"Turn right and we're there," the detective agreed.

"Let's go then!" Harry said. "Allons-y!"

Sherlock started to walk, then stopped. "That was French," he told Harry. "Why didn't it translate into English? It's not Gallifreyan."

Harry rolled her eyes. "Seriously?" Sherlock continued to look at her questioningly, and she sighed. "I'll tell you as we walk. Come on!"

-o0o-

A quarter of an hour later, the time-travelling trio stood in front of 221B Baker Street, staring up at the familiar brick building. Well, familiar to most of them, at least.

"There's a museum here, normally," Harry commented. "It opened in 1990. I was there. Good ceremony."

"1990 was when I first met Mrs Hudson," Sherlock remarked. "She'd just bought this place then."

John and Harry exchanged a glance. "Curiouser and curiouser," Harry murmured, heading towards the door.

John followed his sister up the steps, and raised a hand to knock. He hesitated, his fist hovering a few inches from the door.

He glanced around, looking at Harry and Sherlock. "I can't do it," he muttered.

"Give it here," Harry muttered, pushing him aside. She, too, raised her hand, and was just about to knock when a greeting came from behind her. "Awright there?"

She spun around. A young man stood on the pavement behind Sherlock, watching her amusedly. "There ain't no use doin' that," he said helpfully. "That place 'as been empty for years, mate. No one there to hear ya."

"Oh," Harry said. "Um, would you happen to know anything about the person who used to live here?"

The man shrugged. "Nothin' I can tell you. Don' know if anyone ever lived there, if I'm hones' with ya."

"Thank you, sir," John said in a friendly tone. "Might I inquire as to your name?"

The man snorted with laughter. "I ain't no sir, mate," he said. "No sirs around here. I'm Alfie. Alfie Wiggins." He proffered a hand, and John shook it with a grin.

"Here," John said, fishing in his pocket and pulling out a pound and a shilling. "Have a guinea for your troubles, Alfie."

Alfie's eyes widened, staring at the money in John's palm. He glanced up at John's face, then his hand darted out and grabbed the money so quickly that even the two Time Lords did not see him do it. "Thank you, sir," he muttered, and then he was gone, disappearing down the road and around the corner in the blink of an eye.

Harry watched him go with a small smile. "One guinea? Very original of you," she commented.

"Shut up," John told her sternly, beginning to walk away.

"Why are you leaving?" she asked him. "We could still go inside."

"Not now," he told her, glancing around. "We've already attracted some unwanted attention by going to this house. We're going to go back to the TARDIS, and come back after dark. Okay?"

Harry shrugged. "Okay," she said, and began to follow her brother. Sherlock sighed and hurried after them, hoping that the TARDIS would not be as cold as the chilly London streets.

-o0o-

As it turned out, the TARDIS was pleasantly warm inside. Sherlock found himself no longer missing his coat.

"What did you mean, when you said that John was unoriginal?" he asked Harry when they got inside. She stopped in the doorway to talk to him, while John walked past them to the console.

Harry frowned for a moment, then grinned at the memory. "In the original Conan Doyle books," she explained, "Holmes had a band of street children called the Baker Street Irregulars. He would pay them for information, and a guinea was the prize he gave for a vital clue. They were run by a boy called Wiggins. That's where John got the idea from."

Sherlock raised an eyebrow. "Wiggins? I know someone called Bill Wiggins."

"He's a junkie," John said from the console.

"He's a chemist," Sherlock retorted.

"Chemist junkie."

"Chemist, occasional drug user."

"All right!" Harry yelled. "Stop fighting. The important thing here is that once again, your life is following our fiction, which shouldn't happen in any universe, let alone this one."

Sherlock stopped. "Wait. There are different universes?"

John sighed and pinched the bridge of his nose. "Another time, Sherlock. Not now."

Sherlock, remembering that John was in charge, decided to shut up.

Harry wandered over to the console. "All right. What are we doing now?"

"We need to go back to 221B after dark. It's now around three in the afternoon, and it'll get dark in a couple of hours, although we really need to wait until night-time. I think we should wait here, rather than jumping forwards in time."

Harry blinked. "Why would we do that? We have a time machine!"

"I know," John said. "But there's a couple of things I need to do before we go. One thing we're missing is a sonic screwdriver. I presume Dad has his?"

"He did last time I saw him," she frowned. "It's definitely not in here, and it didn't show up in any scans on the dalek ship."

"So it's with him, wherever he is," John mused. "Right. I could probably make a makeshift one, given the right tools. Do you know where the workshop is?"

Harry shrugged helplessly. "No idea."

At this point, Sherlock stepped forward, hand half-raised. "The workshop, if I remember correctly, should be through that door," he pointed, "along the corridor a bit, up the first set of stairs, and make three right turns." He delivered the directions briskly, with a small smirk growing on his face. He was glad to be back in his element, knowing more than other people.

"Uh, thank you," John said. "Thanks, Sherlock. Really." And with that, he headed off through the door towards the workshop, leaving Sherlock and Harry alone once more.

Harry turned to Sherlock. "You've got a good memory," she commented.

"I do my best," he replied.

"Yeah, John said you were a clever one," she said. "It must be difficult for you, suddenly discovering that your best friend is smarter than you."

"Well, this is certainly a new experience." Sherlock wasn't normally one for discussing feelings, but then again today was not a normal day. "Difficult is not the word I would use to describe the situation."

"What word would you use?"

He considered the question for a moment. "Illogical," he decided. "I would say it is illogical."

Harry raised an eyebrow. "Illogical. All right then, Spock."

"Spock?"

In answer, Harry raised one hand, palm forward, with her middle and ring fingers parted. "Surely you've heard of Spock," she said incredulously. "Star Trek? I studied him in school."

"You studied an Earth science fiction television show at school?" Now Sherlock looked incredulous.

"We got to choose another planet." Harry shrugged. "I disliked the teacher, and he disliked Earth, so I chose that." She wandered around the console, poking at various controls. "I wonder what that one does?" she murmured.

Sherlock said nothing, staring upwards at the top of the console. He jumped when Harry spoke to him. "Can you tell me about John's wife?"

"What do you want to know?" he asked cautiously.

"When he was talking about her, he was tense," she explained. "There was something he wasn't telling me. What was it?"

"I really think that would be better coming from your brother."

Harry was walking back around the console, approaching Sherlock slowly. "Mary Watson died, in the original books," she told him. "But she isn't dead, I can tell. Why is John living with you instead of with his wife?"

"I…I really don't think John would thank me for telling you…" She was standing right in front of him now, in a position that was similar to the way Irene Adler would stand, but with a different intention. While Irene had been trying to intimidate him, Harry was merely interested.

"Fine," he relented eventually. "I'll tell you, if you promise not to let John know that it was I who told you."

"Absolutely." Harry stepped to the side and sat down in the jump seat, looking up as if waiting for a story.

"All right." Sherlock He paused for a second, working out how to phrase his next words. "Mary Watson is a former foreign assassin who was trying to keep her past secret. She shot me here," he indicated above his heart, "and I nearly died. John left her after discovering her deception, and came back to stay at 221B, although I suspect now that his wife was not his only motivation. Oh, and she is pregnant, a fact which I deduced in the days leading up to their recent wedding."

Harry nearly fell off the jump seat. She stared at him, eyes wide. "Mary's pregnant?" she breathed.

Sherlock fought the urge to roll his eyes. "And she is a former assassin who tried to kill me."

"And she's human?" Harry said for confirmation.

"And I thought I had trouble sticking to the subject at hand," Sherlock muttered, leaning on the console. "Why does it matter whether she is pregnant?"

"If she is, the baby will be half human," Harry said soberly, "and half Time Lord."

Sherlock's hand slipped off the console. He stumbled for a moment, before hastily righting himself. "I never thought about that," he half-whispered. "What will that mean? How prevalent will the Time Lord part be?"

"Difficult to say," she mused, standing up. "I don't remember there ever being a half human baby before. There have been other species, of course, but…I don't know. D'you think John has thought about that yet?"

"We could ask him," Sherlock suggested, turning to head for the door; but Harry stopped him with a gentle hand on his arm.

"Not a good idea," she advised. "John tends to get a little…stroppy when he's building sonic instruments."

As if on cue, they heard a crash followed by a yell of frustration echoing through the TARDIS. Sherlock flinched, and Harry looked at him with an expression that said what can you do?

"I see what you mean," Sherlock said delicately, turning back around. "We should leave him."

"Good thinking." Harry sat back down in the jump seat, and gestured to the seat next to her, indicating that Sherlock should sit down also. He did so carefully, facing slightly away from Harry. They settled down to wait until John had finished making a sonic screwdriver, however long that would take.

-o0o-

A couple of hours later, John emerged from the workshop, arm held aloft in triumph. He made his way quickly back to the console room, finding Harry and Sherlock talking animatedly on the jump seat.

"I did it!" he exclaimed, holding his hand out as evidence. In his palm sat a crude-looking instrument, about the size of a screwdriver, with a small red light diode at one end. It appeared to have been cobbled together from various bits and pieces of other instruments, and had a rubber grip that seemed to be fashioned from a melted eraser (Sherlock had experimented with enough of those to recognise a melted one).

Harry's features relaxed into a smile. "Well done," she congratulated him, glancing at her watch. "And in record time, too!"

"Shut up."

Sherlock spoke up. "How does a sonic screwdriver work? I would assume it would emit a high-pitched pulse of some kind?"

"Got it in one," John said. "It emits energy in the form of high-pitched soundwaves, and it's a very useful tool."

"And this can get us into 221B?" Sherlock looked doubtful.

In response, John held up the device and pointed it at the TARDIS door, holding it like one would a laser pointer. He pushed a button on the side, and the red tip lit up, emitting a buzzing noise. He flicked the switch a few times, the pitch of the buzzing higher with each flick; then the door suddenly flew open, exposing the darkened alleyway outside.

Sherlock stared at the open doorway, then at the sonic screwdriver in John's hand, then up at John's face. "That is extraordinary," he said in awe.

"Told you we had a few tricks up our sleeves." The smirk in Harry's voice was audible.

John glanced quickly between them, pressing the button again to close the TARDIS door. "You two had a nice chat, then?"

Harry raised an eyebrow at Sherlock, who was still frowning at the sonic screwdriver. No answer seemed forthcoming, so she spoke up. "It was very educational," she said. "I asked Sherlock about Mary."

John's body tensed up, his manner changing abruptly. "Did you now?" he asked, his voice suddenly dangerously calm. "And what did he tell you?"

By this time Sherlock was watching both of them anxiously, eyes flicking between the siblings, having noticed danger signs in John's behaviour. Harry, however, seemed not to notice anything amiss as she casually said, "He told me that Mary is an ex-assassin who tried to kill him during one of your cases."

For a moment, he seemed almost to relax, until Harry continued, "Oh, and that she is pregnant. With your child." Her expression was calm, passive; but her eyes scrutinised his face carefully.

A muscle twitched in John's jaw. He remained silent.

"Is it true, John?" Harry kept her voice level.

Finally, John sighed infinitesimally. He looked at the ground and hung his head. "Yes," he admitted. "It's true."

"So you're going to make a woman the first ever mother of a half-time lord, half-human, and she doesn't even know you're not human?" Harry demanded. "There's never been anything like this recorded, John. Ever! What were you thinking? You have no idea what the child will turn out like, how Time Lord it will be, how human-"

"DO YOU THINK I DON'T KNOW THAT ALREADY?" John yelled. "DO YOU THINK I DON'T ALREADY FEEL GUILTY FOR SUBJECTING HER TO THIS? DO YOU THINK I DON'T LIE AWAKE AT NIGHT, TRYING TO WORK OUT HOW TO TELL MY WIFE THAT WE'RE NOT EVEN THE SAME BLOODY SPECIES?"

John abruptly stopped shouting, breathing heavily. Harry and Sherlock had taken a step backwards from him, startled by the outburst. He looked at each of their faces, somewhat taken aback by his sudden show of rage.

Still breathing heavily, John leaned backwards onto the console, lowering his eyes to the floor. "I'm sorry," he muttered. "I'm sorry."

Neither responded to him, instead watching him quietly. John ran a hand over his haggard face. His eyes looked old, older than Sherlock had ever seen them.

"I have thought about it, over and over," he said quietly, still looking at the floor. "I've been trying for months to work out how to say something, anything, to Mary. Then the Magnussen case came along, and it turned out that she was hiding her past as well, and…I don't know. There was never a good time. I was focused too much on working out why my best friend bloody existed, and I never told her. It's far too late now to do anything about it." He took a deep breath. "My wife Mary is pregnant, and there's nothing I can do about it."

The silence stretched between the trio, like a yawning chasm, until eventually Harry spoke. "You could tell her," she suggested quietly. "You can't do anything, but you can support her. Tell her everything about Time Lords, about how we grow up and mature, and wait and see. You've created a new species together, unique in the universe. You can discover it together." She moved forward and placed her hand on his shoulder. He tensed, but did not move. "You don't need to abandon your wife, John. You can still help her."

They stayed like that for a few moments, until finally John raised his head and stared into space. "You're right. Of course you're right. I can help her." A hint of a smile appeared upon John's face. "I can help her," he repeated, his voice gaining a little confidence. The life slowly began to reappear in his eyes. "When we get back," he said resolutely, "I will tell her. I will tell her. You see if I don't."

John turned to Harry. "Thank you so much," he said, and held his arms out. She stepped into his warm embrace, and they held each other for several moments.

"I've missed you," he whispered into her ear.

"I can see why," she whispered back. "You clearly need me to be able to do anything."

"Shut up," he told her, pulling back. But the tone was friendly, and they smiled at each other before John turned to Sherlock.

"Sorry for shouting at you," he said awkwardly.

"It's perfectly all right," Sherlock said mildly, "I'm used to you shouting at me."

"Yeah, well sorry anyway." John extended a hand, which Sherlock took firmly in his larger one. They stood for a moment, before Sherlock let go of John's hand and stepped back.

Harry glanced at her watch, specially engineered to tell the local time anywhere in the universe. This watch was her favourite piece of Time Lord technology, not to mention that it was one of the few pieces of Time Lord technology left in the universe. "It should be late enough by now," she told John and Sherlock. "There won't be anybody still outside at this hour."

"Shall we go then?" John asked, and the others nodded. He led the way towards the door.