It was Holmes' face, but not his mien. The cold-blooded reasoner I had known was not at the forefront of this man's personality, but lurked in his eyes at best. They studied me shrewdly from amidst expressive features, who's candor I nonetheless felt I did not like to trust. It was perhaps Holmes' ghost, haunting someone else's body.

"What are you doing here, Watson?" he asked.

The lilt in his voice was unmistakably Irish. He swiveled his head to the side to regard me obliquely as he spoke, in a manner that would be described as reptilian at worst and avian at best.

"I have more reason to ask that of you," I said levelly.

The ghost gestured with the hat in his hand to the headstone we stood before, an incredulous little smile twisting the corner of his mouth without humor. "This is Sebastian Moran's grave," he rejoined.

I replied, voice flat and cold as ice to my own ears, "You're dead."

"So I am." The smile faded.

"Then you will answer first."

Not-Holmes sighed, settling the hat over his wind-tousled dark hair and slipping his hands into his overcoat pockets. He looked down at the grave, once animated features now inscrutable. "You visited my grave, once."

I shook my head. "I visited both of them once I learned the truth."

"Then," he replied, "you understand."

"Moran was your friend."

He hesitated in a manner that was infuriatingly Holmsian, then answered with a frankness which was not. "Yes."

"And I killed him," I owned without remorse.

"No," said my companion, "a jury killed him. He would never have appeared before them, were it not for your involvement – but the Adair business was foolishness on his part, and he ought to have known it. I am the one person who could have prevented it all, so that is where the blame lies."

"Holmes -" I began to protest, habit already having formed some reassurance against this familiar sort of self-recrimination on my lips, but was cut off by the piercing, grey-eyed look I was suddenly fixed with for this as much as by realizing my error.

The man who was not Holmes all but gaped at me in surprise for a moment before breaking into a grim smile I had never seen before on his countenance and chuckling wryly.

"Oh, Watson," he said. "Good old Watson." The smile was exchanged for a frown and he sobered before adding: "I owe you a thousand apologies."

"I imagine you owe many people restitution for the wrongs you have done them," I said, manner cooling once again, "but in this instance Sebastian Moran is not one of them, and we both know it."

"I abandoned him as surely as I did you when I disappeared," Not-Holmes returned dismally, shaking his head. "I never expected to pay for it."

"Pay?" I exclaimed - shocked, perhaps in light of my own losses, at such self-pity. "You are not the one in the grave."

I had spoken almost without thinking, and was surprised to see the effect of my words. The face of the man beside me darkened suddenly before the aloof mask I had once been so accustomed to addressing over breakfast or across a train compartment descended upon it. He seemed more like Holmes than ever when he turned to me and replied: "You're right, of course. I suppose it has cost me the least, out of all of us. I suppose you have been paying for it as well."

It was difficult to think of how to answer. "I have...grieved, yes. You were – Sherlock Holmes was my friend. My dearest friend." I waved a hand towards the grave. "You understand."

"He was a lie, Watson," my companion said with a gentleness that seemed out of character for both the man I had known and his arch enemy.

"You still look like him," I accused.

"But I am not him."

"Parts of you are. Parts of him were charade, perhaps – but even you could not keep up a total lie for so long. You had to allow bits of truth in."

"You can't even think of what name to call me by," he argued, as though to point out to me the disorder in my own thoughts.

"Exactly so," I nodded. "You remind me too much of him. Part of me is still convinced that James Moriarty murdered him, so I should prefer not to address you as professor either, if you don't mind."

"I don't," the man all but scoffed. "As a title it only serves to remind me of a degree of success I failed to attain."

"I assume you refer to the chair of mathematics you were dismissed from."

"Indeed." He looked at me sidelong again, Holmes in his eyes and Moriarty in his manner. "I suppose you imagine that my dismissal was the result of some gruesome scandal – that some infraction of mine had been uncovered?"

I blinked in astonishment – Holmes had once been accustomed to use the words 'some infraction of mine' to refer to incidents such as setting fire to the drapes or breaking Mrs. Hudson's china – then nodded.

The alien smile flashed across Not-Holmes' features again. "Well, no victim came forward, and no one in my employ betrayed me. It was discovered that my credentials had been falsified. Can you imagine? So great a setback, all over the matter of a simple forgery. My work should have spoken for itself – it was the truest thing I have ever done – but, alas, my origins were found to be too humble, and, what was more, I had embarrassed the venerated academics whose ranks I sought to enter by my deception. That was what cost me the chair."

I stared at the grave for some time, thinking about this and saying nothing, before my companion finally observed: "You're wondering why I'm willing to tell you this."

"You never spoke very freely about your past before," I acknowledged.

He shrugged. "I had quite a bit more to hide, then." He dug a toe briefly into the rain-softened sod at our feet before adding: "And if I were to repay you with anything, I think you would want the truth."

I continued to study the headstone, answering quietly without looking up. "What if I wish to know no more of it?"

The man beside me said nothing for a moment, until I observed his posture shift slightly in my peripheral vision. "Then if I can do nothing more for you," he said, voice even as slate, "I will take my leave."

He turned on his heel to go.

A/N: I use 'Convolution' in the title in the mathematical sense.