"Let me examine the patient," I said.

"You?" he said, sounding altogether less certain.

Put me in the path of danger and I will swear in the ripest Hindi. The man in front of me said his single word in an accent that spoke of education and birth. At times of great stress we all revert to the accents of our childhood. It seemed he was a rogue from choice rather than necessity.

"Did I not mention I was a surgeon?" Opening my coat further, to reveal the gun beneath, I began to push my way through the crowd.

"Look at me," I demanded of the groaning man, and he opened his eyes with a great deal of fluttering and a dying fall of sobs, all the more convincing for being slight.

"Now focus on my finger."

I moved this digit and watched his eyes trail after, delayed by a single second and inclined to roll back in his head. Mind you, good at acting or not, I could always use any man prepared to step in front of charging horses, catapult himself above a carriage and dislocate his own leg on landing.

Gripping that leg, I put my other hand to his knee and pulled, twisted and pushed almost simultaneously. The wretch gave a hideous shriek, more from shock I suspect than anything else and forgot to keep his eyes half focussed.

"See," I said, "good as new." To make my point, I worked his knee as one might work the leg of a horse. In the crowd someone began to clap.

"Those ribs," I added. "How are they feeling?"

His cast his eyes behind me to the fat man who hovered anxiously at my shoulder. Whatever passed between them, the wretch now sprawled on the ground sighed, his face already resigned.

"Better," he said.

"Let me." His ribs were fine, the sponge actually a bladder sewn into the side of his shirt and worked by pressure. Our man with the narrow face and darting eyes was so busy worrying that I might identify the object beneath my fingers, that he entirely failed to notice when I lifted his wallet.

"Nasty swelling," I said, pocketing that object as I wiped my fingers on the side of my own trousers. "Otherwise, just a graze." Helping the man to his feet, I held him steady as he found his balance. It was a nice touch.

"Your name, Sir?"

The man looked at me. "Sigerson," he admitted finally. "Professor Sigerson."

"Professor?"

"An American university. In San Francisco. A thoroughly modern institution." He managed to imbue this description with a level of approval which would have been missing had the words come from my mouth.

"And your friend?"

"My brother," he corrected.

Had someone told me those two men were picked at random from a thousand such, rounded up off the streets of London I would have believed him. The idea that they shared the same blood was an altogether stranger proposition. One man was fat and small eyed, the other tall and beak nosed, with eyes that belonged to an Ottoman potentate.

"Professor Sigerson," I said, offering my hand. "Pray let me call on you to confirm your recovery..."

Needless to say, the address given me was as fake as the name. The house in which this man really resided was behind the new railway station. A shiny brass plate by the gate announced it as the residence of Professor Sigerson, thinker & Dr Sigerson, general physician.

The screws holding this unlikely announcement were new, but a hundred tiny scratches at the four corners spoke of other walls and hurried exits. At least, so Hunter told me when he returned, following them being the task I gave him while I found a blacksmith to repair the broken rim of our wheel.

So, it was entirely my fault the two Sigersons had vanished by the time I presented myself at their door. Stripped bare, their rooms echoed to the sound of my search, even the carpets having been spirited away. A very agitated landlady, who had appeared out of breath, shortly after I had Hunter break down the door, kept demanding of me what kind of fiends stole everything.

"Efficient ones," I told her, although I fear she did not entirely understand my joke. The constable who'd accompanied the landlady began to make notes and, as I listened, her list of items grew longer and ever more valuable.

"I will never get them back," she wailed.

" On the contrary," I said, "you can have them this very afternoon with almost no effort..."

It never ceases to sadden me the things that amaze closed minds. The sun setting over the Hindu Kush, with wild dogs circling the last flames of a fire destined to die before dawn; waves deep enough to swallow St Pauls in one watery gulp; the innocence of a Nepalese child goddess so beautiful grown Generals cry in her presence, such things are put on this earth to stun us. To be amazed by anything less seems an insult to intelligence.

As I suspected, my comment that her goods would be returned proved enough to silence the landlady. Although I then had to explain to the constable that my certainty the carpets could be found at the nearest pawnbroker was more to do with common sense, than any intimate, not to say inside, knowledge of the crime.

"We must be off," I said.

The constable looked as if he might object but changed his mind at a glance from Hunter, who wore the badge of a Queen's Messenger beneath his coat. There my day might have ended, with an interesting meeting and my giving Inspector Lestrade descriptions of the two rogues and an order that I be notified when they were found. And so it would have ended, if Hunter and I had not proved woefully incapable of paying the blacksmith for his work on the wheel.

"Sir?"

I fumbled at the pig-skin bag in my hand and then stopped, angrily. I am not a man who fumbles. In it I felt a map of the empire painted onto silk, my cigars, which actually broke open to reveal sticks of hashish, which the dear Queen herself uses for pain, a little opium, a throwing knife, a set of prayer beads given me by Kais Bey.

Everything was where it should be, except my reward for work well done, the bag of gold I'd gone to Windsor to collect. Apparently, while I was first curing our accident victim, the fat little doctor had come to take a look at my carriage. This, it appeared, was not all he took.

"Sir?" said the blacksmith.

"Here," I replied, impatience winning. With a flick of my wrist, I took the throwing knife and slashed open the bag's handle, revealing a dozen half-sovereigns sewn into a sealed silk tube. I took three coins, more than his work was worth and gave them to the man. "That also buys your silence," I told him, nodding towards the ruined bag.

He left without another word.

It was then I turned to the rogue's wallet and found my first real clue and proof of his name. The clue came in the form of a train timetable and the name from a scrap of newspaper. Sherlock Holmes, younger brother to Mycroft and pupil of Professor James Moriaty. Almost every detail in the report was wrong � the events described took place at St Jean, not Pau, in August 71, not March 72 - but the scribbler was right about one thing, there had been a scandal.

When I put my mind to things I can make them happen quickly. So it proved in engineering my next meeting with the elusive Mr Holmes. The man had money, my money, he had no need to visit the town underlined in his railway timetable, but he would visit it just the same. I'd felt his heart beneath his shirt and it had been racing. He lived for the challenge. No man is so poor he has to jump in front of four galloping horses.