My first foray out of the realm of Merlin (OK it's a crossover of Merlin and Sherlock so I haven't gone that far) it's still kind of exiting though :-)

Please don't ask how or why, it just is. And it's also a one-shot, so it won't be continued in any way, shape or form.

Disclaimer: the BBC got there first

He had thought that the dreams had stopped, it had been months now since he had had a nightmare, and not much longer since he had moved into 221B. But the image of two boys – one wearing very realistic chainmail, the other in a battered brown jacket and tattered blue scarf – holding his flatmate hostage at sword point must have been part of a dream. Even for someone who lived with Sherlock Holmes, this could definitely be classed as a bit weird.

"Hello." It wasn't really what John wanted to say, but it contained less swear words, and was probably more polite.

"Ah, John, excellent timing, could you please explain to these people that holding another at sword point is probably not the best way of getting answers, in fact the act of holding someone under duress is probably more likely to lead to false answers as the captive-"

The one in chainmail pressed his sword more firmly against Sherlock's throat, the threat of imminent decapitation was one of the very few way of actually shutting the detective up. "Who are you? And what is this place, sorcerer?"

"And perhaps a brief education on the benefits of psychiatric treatment." The final word was undoubtedly strained as the blade presses harder against his Adams apple.

"Okay, okay, everybody just calm down." John said, his hands raised in what was usually considered a placating gesture, however, it seemed that he had only achieved to shift the attention from Sherlock to himself, as the broadsword wielding maniac released the detective and brandished his sword towards John instead. The one in the scarf just buried his head in his hand, apparently accustomed to his companion's bizarre behaviour.

It would seem that according to Sherlock the lack of a very sharp, and clearly, very well used sword against your throat was as good as an invitation to start talking. Sometimes the genius was an idiot. "It would appear that you are both under the delusion that you're from the dark ages. I believe that- oh!" he cut himself off this time, the constant deductions that transpired in his mind presenting him with a conclusion that, judging by the look on his face, was at least interesting enough to keep him occupied for a couple of hours. "You don't think you're from the dark ages, youare from the dark ages."

John could generally accept Sherlock's lightning quick deductions, whether it was the nature of an affair, or theft, or even murder the consulting detective was correct almost every time, but that two men standing in their living room, one wielding a dangerous weaponry, were from another time? That couldn't be right. "What?"

"Look John, really look." John tried, he really did, but whatever Sherlock had seen to lead him to the startling conclusion of time-travel, instead of just a couple of escaped nutters, was way beyond John. Sherlock gave an exasperated sigh and flung himself onto the sofa.

"Their clothes, John, clearly of poor quality cloth, but well worn. Not an outfit for fancy dress then. His chainmail," he gestured to the one wearing the aforementioned armour, "it's real, must be heavy, but he doesn't seem to notice the weight. So he wears it a lot. The dark-haired one," he gestured to the one wearing the scarf "he's standing slightly behind the blond and waited for him to start the conversation, so a servant. No one in this day and age who is rich enough to afford servants is going to prance around London in full armour. So either I'm wrong, or there is something fundamentally wrong with the nature of time and space."

It was actually hard to reason which possibility was more likely, everything Sherlock had said had made sense, but time-travel? Really?

The knight and his servant merely looked stunned. It was nice for John to remember what it had felt like to be unfamiliar with Sherlock's astounding mind. The feeling was short-lived however as the dark-haired boy spoke for the first time since John had entered the room.

"Arthur, if he's telling the truth, it wasn't them who brought us here. You can probably stop threatening them." John started to wonder if Sherlock's original assessment of their relationship was altogether correct, the boy seemed far too familiar with 'Arthur' to be just a servant.

Arthur lowered the sword, but it remained in his hand and was not returned to the loop on his belt that was evidently designed to hold the weapon. "How do I know I can trust you?" his voice was laced with the trepidation that John had often heard in the words of the soldiers that had been in Afghanistan for too long, the ones that had learnt the hard way that even your closest friends could turn out to be the enemy.

John decided that it was probably best that Sherlock not try his hand at diplomacy. No matter how much practice made perfect, there was a time to practice social skills, and the time when the other guy had a sword was not it. "I'm John Watson, that idiot over there is Sherlock Holmes. I don't have a reason for you to trust us but I give you my word that we will not try to harm you." He shot a warning look at Sherlock, just in case the detective had any ideas.

"Arthur Pendragon." he waved the sword vaguely in the black-haired boy's direction "He's Merlin, my manservant." John, tried not to sigh in relief, as long as they could keep the conversation civil there was, hopefully, very little chance that any blood would be spilled.

"Okay, good, do you know how you got here?" hopefully if he kept the conversation flowing Sherlock wouldn't manage to get a word in edgeways. He should probably have known his audience better though, because as soon as the words had left his lips the lanky git gave an impatient snort and went full throttle into a rather complicated explanation about mud, dead leaves and the ionising qualities of time-slips (seriously? The guy knew about some half-baked scientific theory but not Copernicus' basic model of the solar system*) on the nitrogen in the atmosphere of the flat.

Merlin and Arthur had probably understood less than half of what Sherlock was spouting, the genius didn't seem to remember that they were, in fact, from an era where the phrase 'instabilities in the fabric of the space-time continuum' meant about as much as forty-two.

Arthur seemed to get annoyed about halfway through the rant and interrupted Sherlock, a phenomena John had thought impossible. "Yes, well that's nice but do you know how we can get back home." He held up his hand to silence Sherlock before there was another tirade of baffling statements. "In simple terms please." John got the feeling that Merlin might have been smirking at his master's admission of ignorance if their circumstances had not been so dire.

"I don't know, it's possible that the-" there was a pause as Sherlock tried to find the right, simple word "gap in time will open up again and take you back to wherever you came from, or you could be stuck here forever." He had barely finished the sentence when an eerie golden glow surrounded both the knight and his servant, and both disappeared from their lives forever.

If John had not been living with Sherlock Holmes, the worlds greatest and in fact, only consulting detective, he might not have noticed the way in which Merlin had been muttering, almost unperceivably under his breath, or the way that his eyes had shone gold a moment before the glow had surrounded them. But because he had not only picked up a small percentage of Sherlock's incredible observational skills, and remembered a half forgotten fairy tale about a king named Arthur, and his advisor Merlin, he was perhaps less shocked than he should have been at having the two strangers vanish once more.

"Well that most certainly alleviated the boredom for one night." Sherlock said, the gleam in his eyes confirming John's fears that the next few week of his life would involve a large quantity of phiysics that he had no hope of understanding.

Oh please God let there be a murder…