The issue raised in this Chapter is, perhaps, the only aspect of detective work not subordinate solely to deduction and common sense, which is why the Chapter was written in a manner somewhat different from the rest of the book.

The area of ethics is vast and as yet uncharted, though there are tacit cornerstone conventions that complement the official code of conduct. The unofficial investigator, on the other hand, can and occasionally does find himself in a position where those are inapplicable, with only discretion and integrity to guide him. It is not, strictly speaking, the line between Good and Evil; nor it is the common condition of being threatened or bribed. Those are simple to decide upon. There is, however, the odd instance such as the one I will now discuss in great detail, but necessarily sketchily, even reverting to the style preferred by writers of fiction, for the student to choose the course of action for himself. The delicate nature of the case has, of course, prevented me from disclosing any name save mine own.

It was the spring of 189..., and I had earned myself a vacation from both public and governmental duties by having just helped the Force to capture of the late Professor Moriarty's ring of criminals. I was to spend it in a remote location. Inspector Patterson, in charge of the investigation, could not spare a man to accompany me on my travels as far as the seaside, in case there were, as there often are, members of the gang to escape justice, and thus I was going to leave in the guise of a Capt. Peter Basil.

My plans were adjusted the very evening I was packing my chest.

'Mr. Holmes, a visitor would like to speak to you on a matter of the utmost importance.'

With that, and without waiting for a reply, Mrs. Hudson (the praiseworthy landlady I had been the tenant of for most of my career in London) left a card on top of the evening paper, neatly covering the tiny advert about Patterson's success, and departed.

I was not too eager to meet this visitor. However, there was little I could do, for he was already coming in and looking around avidly.

A rather non-descript person around thirty years old, neat in appearance and speech, with greying hair already thinning, he appeared the picture of decorum. His pale eyes belonged to a much younger person, and his bearing indicated strong will and optimism. He haled from Scotland, but there was little of his motherland about him except his surname.

He never interrupted anybody; rather, he gave a chance for anyone to contribute before him. Perhaps it was what earned him a beat of silence every time after he finished talking. Despite his successful career as a money-lender, he had not lost – and, as I came to realise, indeed acquired – faith in the goodness of Man. He also proved to have a life-long reputation of Spartan fairness, only loaned to the poor, and never asked for more than was his due.

Mr. Henri Watson courteously allowed me to retain the appearance of a captain, and related his troubles in a speedy and effective fashion. His brother, a Doctor by trade, was, in his considered opinion, digging himself a pit by dabbling in shady activities that had something to do with opium dens and people going missing. I did recall a recent scandal involving a subaltern disappearing the night after coming to the capital, and Mr. Watson frankly admitted that his wayward brother could have had a hand in that. Boasted, even.

He hastened to reassure me, though, that the man was not to be put behind bars.

'I swear by our father's grave,' he said simply and with great dignity, 'he is as honest as Joseph. Hasn't once overstepped the law, in spirit or in letter.'

'Was he compromised in any way, then?' I asked, bewildered.

'Not yet. Rather, I am afraid he would be killed by his, ah, competitors.'

'A valid concern. Well. I will look into your affair, but I will reserve the judgement for later.'

His face clouded. 'Judgement is something best left to judges, Mr. Holmes. Mark my words, we mere mortals are not cut out for it.'

He went then, and I made the changes to accommodate his request and, I have to confess, to satisfy my own curiosity. For I had, unbeknownst to my client, an inkling of what lay ahead of me; rumours and hearsay, but from that I could already gather that for someone who wished to keep a low profile for a while, Dr. John Watson's little world would make as fine a cover as any Continental resort.