He was dressed in a long crimson dressing gown, under which I could see that he was already prepared for a formal engagement of some kind. Beneath the open silk gown he was wearing some sharply-pleated grey pinstripe trousers, white cloth spats, a starched dress shirt and a black bow-tie. I had already noted the black frock-coat which Mrs Hudson had placed on a hanger to his left and the top hat which Holmes had positioned, somewhat incongruously, on the head of a plaster death mask, which sat in pride of place on the mantelpiece.

“What is ‘splendid’, Holmes?” I queried, with obvious irritation, having waited for further words or some suitable explanation which had not been forthcoming.

Holmes seemed impervious to my agitation. “It seems that Inspector Lestrade has a rare murder mystery for us to consider, Watson. I apologise for not having explained matters more fully in my earlier telegram, but I need you to meet with the good inspector when he arrives here at nine o’clock this morning. This piece in the Daily Telegraph gives us some indication of the puzzle which Lestrade is faced with and the reason he is so keen to seek my assistance.”

I resisted the temptation to ask him about the newspaper article and went straight to the crux of the matter: “So, you’ve called me here to meet with Lestrade at the appointed time, so that you are free to swan off to some prior engagement. Well, I must say, Holmes, I find this most irregular. While my medical practice is quiet at the present time, you know that I am not without commitments, engagements and responsibilities of my own.”

Holmes seemed genuinely stunned by my rebuke and a look of concern crept over his pallid-white features. “My dear Watson, it seems I have been very thoughtless in taking your assistance for granted and presuming that you would be able to stand in for me. I meant no offence, but believe this will be an affair worthy of our attention, since it will be the first time that we have heard from Lestrade since April of this year, when we were involved in what you described, very commendably, in your published accounts as The Adventure of the Empty House.”

Ever susceptible to my colleague’s effortless flattery, I was determined to hold out a while longer. “That’s all well and good, Holmes, but you haven’t even told me what this other appointment is and why you cannot meet with Lestrade yourself.”

“It is a small distraction, I assure you. I would much rather meet with our police colleague and had planned to do so when I responded to his request yesterday evening. However, about nine o’clock last night, I received a hasty and unexpected visit from my brother Mycroft. He informed me, rather belatedly, that I am required to attend a lunch appointment at the Danish Embassy today, at which I will be awarded the Order of the Dannebrog. I was told about the honour some weeks ago and had asked for it to be posted to me. Mycroft explained that I was likely to cause offence - and something of a diplomatic incident - if I continued along that path and persuaded me instead to accept the award in good faith from the King of Denmark, Christian IX, who is visiting London this week.”

I could scarcely believe that Holmes had not thought to mention this news earlier and expressed my astonishment at his reticence. He explained that Danish protocol had prevented him from talking about the matter until the award had been received. “In any case,” he added, “The honour was given for my very inconspicuous assistance in saving his youngest son, Valdemar, from some risky investment schemes which contributed to the collapse of a major commercial bank in Canada - an entanglement which would have resulted in considerable public scrutiny and financial ruin for the prince. The King has demanded that both the affair, and my role in resolving it, should be kept from the public gaze.”

“Understood, Holmes, but you know that I could have been relied upon to be discreet. There was no need to act so furtively.”

“I realise that now, but my primary concern was to ensure that Lestrade was not put off in coming to us with his case - he trusts and respects you as much as he does me. I need hardly tell you, that I would rather be presented with a single, intangible mental challenge to flatter and sustain my ego, than I would a dozen knighthoods. I seek stimulation not adulation.”

Realising this to be the case and having no wish to continue to chastise my colleague, I turned my attention to the newspaper and asked Holmes to relay what had been printed in the Daily Telegraph. Having lit his favourite churchwarden and taken two or three puffs of the pipe, he read out the news item:

Mysterious Death at Ravensmere Towers

Detectives from Scotland Yard were called yesterday afternoon to the prestigious new office building of Ravensmere Towers near Hyde Park, following a report of a fatal shooting.

While details remain sketchy, our chief reporter understands that the incident is being treated as a potential case of murder, since no firearm was found near the body. The victim of the shooting was a Mr Edward J Flanagan, an Irish national, who occupied the first floor office of Ravensmere Towers, where he ran a successful business exporting English porcelain to the United States.

Detectives admit to being baffled by the circumstances of the death. The building is accessible only from the ground floor, the sealed entrance to which is controlled by a vigilant concierge. He has stated categorically that beyond those few personnel occupying the plush offices, no one entered or left the building during the time the shooting is believed to have taken place. However, when the Scotland Yard men, led by the very capable Inspector Lestrade, conducted a thorough search of the building, they were unable to find the illusive gunman.

The only other paying tenants of Ravensmere Towers are three brothers in their forties, who operate a depository for rare books on the second floor. They claim to have heard a single, very audible shot at around eleven o’clock yesterday morning. Some moments after this, Mr Chester Godbold - the eldest of the trio - ventured out of their rooms in order to determine the source of the noise. Having done so, he claims to have caught a glimpse of a man holding a revolver, running up the stairs to the third floor. The man was said to be wearing a heavy grey overcoat and a large tweed hat which covered his head and the sides of his face and prevented Mr Godbold from seeing more of his features.

Inspector Lestrade was reluctant to say any more about the supposed crime at this juncture.

Readers may remember that Ravensmere Towers was opened at the start of this year to some fanfare. It is said to be one of the most impressive modern buildings in the capital. Its offices are fully-equipped with electric lighting and power and all upper floors are accessible via a hydraulic-powered lift, or elevator, in addition to a traditional stairwell. The owner and property developer, Mr Archibald Cartwright, occupies the third floor of the building, and was said to be ‘deeply saddened’ by the events and has pledged to do all he can to assist the police in bringing to justice the man responsible for the shooting.

“Well, what do you make of it, Watson?” queried Holmes, placing the open newspaper on the table in front of him.

“Quite remarkable. Lestrade and his men were unable to find any lone gunman, so unless the concierge is mistaken - or had, indeed, carried out the shooting himself - the assailant must have been one of those within the building at the time.”

“A perfect summary, my friend. We will certainly need to ascertain whether the concierge can be trusted and whether he could have been mistaken about the apparent security of the building. Beyond that, it will be imperative to find out three things: firstly, some further information about the victim, this Mr Flanagan; secondly, full intelligence on the other occupants of the building and, crucially, where each was at the time of the shooting; and lastly, precise details of the layout and accessibility of the ground and five upper floors of Ravensmere Towers.”