Part Five

And I am undone; for nothing had prepared me for the fiery touch of his wondrous mind. - The Unicornis Notebooks of Magnalucius

John followed Sherlock, tracing the signal of Jennifer Wilson's phone on the computer (bless humans and their technology, bless them, bless them), shouting directions at a harried taxi driver and, over Harry's phone, at an astounded Lestrade (it was a good job that Sherlock had let him keep the D.I.'s ID he'd nicked). Five senses, luck, and GPS – it wasn't quite how he used to do things, but it would do.

Luck is a tenuous thing, though, and fickle. The unicorn could feel it slipping from him as he leapt from the cab, throwing a careless handful of notes at the driver, as ran up the stairs and down darkened corridors, peering into rooms where shapes were defined only by the faint street light seeping in through the windows. He was almost certain that he would be too late and find Sherlock dead or worse, and his heart gave a very human wrench between his very human lungs at the thought.

It was almost a relief when he found the man, but the relief died quickly because he was seeing Sherlock through the window, in the room directly opposite his, in the building that he hadn't entered because it had been a fifty-fifty chance and his luck had turned sour at exactly the wrong moment. There was another man in the room with Sherlock – his Sherlock now, and so the unicorn claimed him – and John saw instantly that he was carrying the dragon-scent, the stuff wafting off of him like fifty kinds of crazy.

Could be dangerous, the consulting detective had said, and he couldn't have had any idea how dangerous things would turn out to be. In his own shape, his old shape, John Watson would have crashed through the windows, charging through the space between the buildings as though things like gravity didn't matter, to defend Sherlock with horn and hooves and a mind that had been old before the world was formed. But as it was, he was confused and lost and, yes, frightened, because the reek of dragon in his nostrils brought that night in Afghanistan back to life. He'd lost almost everything he knew that night, and he knew, as he called Sherlock in a futile attempt to get his attention, that he was inches away from losing more than everything now.

Could be dangerous. On the strength of that text, he'd brought his gun along, asking the ever so obliging woman in the black dress to make a detour on the way back to Baker Street so that he could pick it up, and he pulled it out now as Sherlock held a small white pill up to the light. The weapon felt strange in his hand, cold and grim and heavy, and he prayed as he had never needed to pray before that he would get things right.

The bullet went through two window panes and the cold night air, past Sherlock, and the way the other man dropped made it clear that it found its target. John didn't wait around to see the results of his handiwork. He'd killed before – the horn wasn't purely decorative and the point on it was very, very sharp – and always in defense of his charges, but he'd never been in a position where he'd have to answer for his actions. The law was going to be less than happy with him, he knew that much about modern police work, but he had done what he'd needed to do to keep his charge safe, and that was what mattered.

Yes, he was very loyal, very fast, just like the man with the brolly said, and, apparently, murderously protective in the bargain. It didn't bother him one bit – it was what he was made for, after all, and it was hard to shake the habit even if was wearing a different skin. And, going by the smooth way Sherlock took the matter in stride, how he diverted Lestrade's attention from him, and the infuriatingly smug way he asserted that he'd expected John to show up, it didn't seem to bother him either.

They walked away from the crime scene, laughing even after that, and went to get themselves a takeaway dinner from the Chinese place Sherlock had mentioned. Back at 221 B, the self-made consulting detective ate with chopsticks, skillfully wielding the things with his long fingers while John did his best with a fork. They talked until it was so late that the night was threatening to turn into morning, and it was so easy, so natural that John found himself asking the question that had been tickling the back of his throat ever since the lab at St. Bartholomew's.

"Do you know what I am?" he asked. It slid out on the lateness of the hour, and everything that had happened to them and between them that day, and maybe, just maybe, on a tiny hint of desperation. And Sherlock stared at him, a baffled look sitting uncomfortably on his face. The unicorn tried not to be disappointed. It was too much to ask, after all, even of this most brilliant of men. "No, never mi—"

"Unicorn. From the Latin unicornis, meaning 'one horn,' referring to a mythical horned beast, often said to resemble a horse, but I think that's a load of rubbish. And you are certainly older than the word." Sherlock's fingers brushed the barely-there bump on John Watson's forehead, which was all that remained of the horn his kind was named for, and he frowned a little, as if in consternation. "Of course I saw it. I don't know how you got like that, I don't know what you're doing here, but I saw it. Did you think I missed it?"

"Yeah, actually, I did." John Watson smiled. "Good to know I was wrong."

He spent the night on the sofa of 221B, and in the morning he moved in properly, ferrying his clothes, his laptop and the rest of his earthly possessions to Baker Street in a large, black taxi. It was an adventure such as he hadn't had for an age.

A flawed man and a damaged unicorn. John Watson figured that, for either of them, it could have been worse. And as far as he was concerned, it certainly couldn't get any better.