One morning, towards the end of July, I received a strangely-worded letter, written in a foreign hand, asking me to call at an address in Pembroke Road, Kensington, and signed "Sonia." The missive, which had been left at my flat by a commissionaire, stated that the matter upon which the writer desired to see me was extremely urgent, and contained a request that I would telegraph a reply. This I did, accepting the appointment, for, on reflection, I had a very dim recollection of having, at some time or other, written officially to someone named "Sonia," and the letter aroused curiosity within me. That night, at the time she named, I found myself before a large, substantial-looking detached house, situated in the quiet, rather unfrequented thoroughfare off Earl's Court Road, a house which, to my excited imagination, bore external evidence of mystery within. Why such thought should seize me I know not. Perhaps it was because the writer of the letter was unknown, and the object of my visit at present unexplained; nevertheless I entered the small garden that divided the house from the roadway, and, ascending the steps, rang the bell. My summons was immediately answered by a neat maid, to whom I gave my card, and next moment I was ushered into a well-furnished drawing-room, dimly lit by one tall, shaded lamp, the light of which was insufficient to illuminate the whole room. For a few moments I remained alone in wonder, when suddenly the door opened, and there entered an extremely pretty girl, scarcely out of her teens, dark-haired, with clear-cut features, bright eyes, and a delicately-rounded chin. It struck me, however, even before she spoke, that in her face was a strange expression of unutterable sadness, a look that told of long suffering and intense agony of mind. Her mannerisms were those of a foreigner, her _chic_ was that of the true Parisienne, her dress of black silk crepon was plainly but well made, and the fact that she spoke in broken French was, next second, conclusive. "Ah! You have come, m'sieur. You are indeed very good," she exclaimed, with a charming accent, her skirt rustling as she advanced to greet me. "I am at your service, mademoiselle," I answered, bowing, at the same time accepting the seat she offered. "Well," she commenced, with a smile, slowly sinking into an armchair near me, "when I wrote to you I feared you would not come. You have been so good to me already that I fear to ask any further favour." "I must ask your pardon, mademoiselle," I said, "but I really am unaware that I have ever rendered you any service." "What, do you not remember?" she cried. "You, who were so good to my father and myself; you, to whom we both owed our lives." "I certainly have some hazy recollection of your name," I answered, puzzled, "but try how I will, I cannot recollect in what connection it has come before me."