The same day there arrived through the post a small cardboard box addressed to me, which I found to contain a very large and lustrous pearl.
No word of writing was enclosed.
Since then every year upon the same date there has always appeared a similar box, containing a similar pearl, without any clue as to the sender.
They have been pronounced by an expert to be of a rare variety and of considerable value.
You can see for yourself that they are very handsome."
She opened a flat box as she spoke and showed me six of the finest pearls that I had ever seen.
"Your statement is most interesting," said Sherlock Holmes. "Has anything else occurred to you?"
"Yes, and no later than to-day. That is why I have come to you. This morning I received this letter, which you will perhaps read for yourself."
"Thank you," said Holmes. "The envelope, too, please. Post-mark, London, S. W. Date, July 7. Hum! Man's thumbmark on corner - probably postman. Best quality paper. Envelopes at sixpence a packet. Particular man in his stationery. No address.
"Be at the third pillar from the left outside the Lyceum Theatre to-night at seven o'clock. If you are distrustful bring two friends. You are a wronged woman and shall have justice. Do not bring police. If you do, all will be in vain. Your unknown friend.