Shortly after this interview, the duchess’s guests began to arrive, and soon the house was loud with the buzz of conversation, as informal groups gathered here and there. At a large table at one end of the long drawing room, the imposing figure of the Duchess of Pont’s butler presided over a steaming, aromatic bowl of punch and a forest of bottles of every shape and size. I looked about for Princess Zelda, but she had not yet arrived, so, with a glass of punch in my hand, I took the opportunity to move about the assembly and make a few general observations.

I doubt if I have ever been quite so well turned-out as I was on that evening, but for all the starching and pressing and polishing that had gone into my evening dress, I still felt somewhat plainly attired in that august gathering. There was scarcely a man there who was not decorated with medals, sashes, badges and ribbons, and it was certainly difficult to believe that somewhere among them was a spy whose intention was to pass on secret documents. Discreetly, as I hoped, I moved from room to room, standing now on the fringe of one group, now on the fringe of another. One thing I dreaded was being asked questions about myself, for I was not confident that I could explain very convincingly the reason for my presence. Now and then, I observed Holmes in the distance. He appeared to be moving about the assembly much as I was, occasionally pausing briefly to speak. Once or twice I passed him in a doorway, but I was under strict instructions not to communicate with him unless the matter was urgent, so I did not acknowledge him.

I had just returned to the long drawing room when I found myself drawn into a discussion on medical matters. I chanced to mention that I had served in the Army Medical Department in Afghanistan, and almost at once regretted it, for the man standing next to me, a very large, red-faced man with a monocle in his eye, at once introduced himself, and with a sinking feeling I learnt that he was the commanding officer of that very service. Evidently assuming that if I had been invited to the duchess’s soirée I must have some worthwhile views to impart, he requested my opinion as to the future of the Army medical services. Fortunately, there had recently been some discussion in the press on this very subject, so I was able to make one or two observations that did not sound too foolish, but it was with a feeling of some relief that I managed to extricate myself from the conversation.

Just as I had succeeded in doing so, there came a momentary pause in the babble of voices. I turned my head, to see that Princess Zelda, instantly recognizable from her photographs in the society press, had just entered the room in the company of a dapper little man with a waxed black moustache. For a moment, it appeared that every head in the room turned her way, the male heads no doubt in admiration, the female heads in disapproval, then conversation and discussion resumed again, and the drawing room once more took on the sound of a particularly agitated bee hive.

For some time, as discreetly as I could, I observed her progress about the assembly, as she exchanged greetings and brief remarks with a great many people. I was watching her from the opposite side of the room when she abruptly turned and our eyes met. Feeling my cheeks begin to burn, I quickly looked away and made a pretence of studying a painting on the wall. Moments later, I became conscious of someone standing beside me, and a soft but firm voice spoke in a foreign accent from over my shoulder.

“I do not believe we have met.”

I turned to see the Princess Zelda eyeing me with an expression of curiosity. In what I confess was a state of some confusion, I introduced myself.

“An Army surgeon?” she repeated with a smile. “That must have been very interesting!”

“‘Interesting’ is not perhaps the first word I should think of to describe it,” I responded in a dry tone, and made some reference to the enormous amount of travelling which my military career had involved.

“Ah, travelling!” she interrupted. “That can be so tiring! I leave England tomorrow for the Continent, and I am not looking forward to the journey.”

“That is understandable,” I responded, a little nonplussed by the way the conversation had shifted so abruptly from my military experiences to Princess Zelda’s own proposed journey.

“I take a train in the morning,” she continued.

“I understand that the weather in northern France has been much the same as in England,” I remarked, unable to think of anything else to say.

“Has it really?” said she, looking at me as if I were a complete idiot. “How fascinating!” she continued, turning her head and moving away from me. “Do excuse me. There is someone I must speak to.”

As she drifted away across the room, I realized that my hands were trembling. I made my way to where the duchess’s butler presided over the drinks, requested a whisky and soda and retired to a quiet corner to reflect on my encounter with Princess Zelda. It was clear that despite my efforts at discretion, she had seen that I was watching her and had wanted to know who I was. It was probable, then, that, as we had surmised, she did not know the identity of the intermediary who would pass the papers to her and had thought I might be he. There had been something oddly insistent in her manner of speech, as if she had wanted me to say something that would identify me to her. This observation seemed to me important enough to warrant my telling Holmes, and I went in search of him. Unfortunately, he was nowhere to be seen, and, giving up the search for the moment, I returned to the main drawing room.

The room was now full, and the noise of conversation was almost deafening. The Duchess of Pont herself was sitting in a large group at one side of the room, having what appeared to be a very animated discussion. A little distance away, I descried the Princess Zelda, talking to a tall, thin naval officer. I drifted that way.

I had attached myself to a circle of people discussing the Balkan question, chiefly because it was the nearest I could get to the princess without attracting her attention, when I saw her turn away from the naval man much as she had turned away from me. As she did so, she was approached by an Army officer, resplendent in red tunic, medals and ribbons. As best I could, I closed my ears to the conversation being pursued in front of me, took half a step backwards and endeavoured to eavesdrop on the conversation behind me.

“Colonel Fitzwarren,” I heard Princess Zelda’s new companion say as he introduced himself.

The two of them exchanged a few pleasantries, then the princess again contrived to turn the conversation to her impending departure for the Continent.

“I take a train tomorrow morning,” I heard her say.

“Is that the nine-thirty-five?” asked Colonel Fitzwarren.

With a sudden thrill that almost took my breath away, I realized that he had used the numbers the parrot had repeated to us.

“No,” the princess answered, “the eleven o’clock from Victoria.”

“Are you travelling to Paris?” he asked.

“No, to Venice,” she responded. “I am spending Christmas with friends there.”

“Ah!” said he. “Beautiful Venice! I, too, have a friend there. I wonder, madam, if I might possibly request a small favour?”

“Certainly,” said she. “What is it?”

“I have written a letter to my friend, but I am a little late in posting it, and besides the Continental posts are unreliable at this time of the year. I wonder if you could possibly take it? I could wire my friend to meet the train.”

“By all means,” said the princess, the sparkle of laughter in her voice. “Do you have the letter with you this evening?”

“As it happens, I do.”

“Then instruct one of the servants to place it with my belongings in the cloakroom. What is your friend’s name, by the way, Colonel?”