“Exactly! But does the name Isadora Klein convey nothing to you? She was, of course, the celebrated beauty. There was never a woman to touch her. She is pure Spanish, the real blood of the masterful Conquistadors, and her people have been leaders in Pernambuco for generations. She married the aged German sugar king, Klein, and presently found herself the richest as well as the most lovely widow upon earth. Then there was an interval of adventure when she pleased her own tastes. She had several lovers, and Douglas Maberley, one of the most striking men in London, was one of them. It was by all accounts more than an adventure with him. He was not a society butterfly but a strong, proud man who gave and expected all. But she is the ‘belle dame sans merci’ of fiction. When her caprice is satisfied the matter is ended, and if the other party in the matter can’t take her word for it she knows how to bring it home to him.”

“Then that was his own story- -”

“Ah! you are piecing it together now. I hear that she is about to marry the young Duke of Lomond, who might almost be her son. His Grace’s ma might overlook the age, but a big scandal would be a different matter, so it is imperative- - Ah! here we are.”

It was one of the finest corner-houses of the West End. A machine-like footman took up our cards and returned with word that the lady was not at home. “Then we shall wait until she is,” said Holmes cheerfully.

The machine broke down.

“Not at home means not at home to you,” said the footman.

“Good,” Holmes answered. “That means that we shall not have to wait. Kindly give this note to your mistress.”

He scribbled three or four words upon a sheet of his notebook, folded it, and handed it to the man.

“What did you say, Holmes?” I asked.

“I simply wrote: ‘Shall it be the police, then?’ I think that should pass us in.”

It did - with amazing celerity. A minute later we were in an Arabian Nights drawing-room, vast and wonderful, in a half gloom, picked out with an occasional pink electric light. The lady had come, I felt, to that time of life when even the proudest beauty finds the half light more welcome. She rose from a settee as we entered: tall, queenly, a perfect figure, a lovely mask-like face, with two wonderful Spanish eyes which looked murder at us both.

“What is this intrusion - and this insulting message?” she asked, holding up the slip of paper.

“I need not explain, madame. I have too much respect for your intelligence to do so - though I confess that intelligence has been surprisingly at fault of late.”

“How so, sir?”

“By supposing that your hired bullies could frighten me from my work. Surely no man would take up my profession if it were not that danger attracts him. It was you, then, who forced me to examine the case of young Maberley.”

“I have no idea what you are talking about. What have I to do with hired bullies?”

Holmes turned away wearily.

“Yes, I have underrated your intelligence. Well, good-afternoon!”

“Stop! Where are you going?”

“To Scotland Yard.”

We had not got halfway to the door before she had overtaken us and was holding his arm. She had turned in a moment from steel to velvet.

“Come and sit down, gentlemen. Let us talk this matter over. I feel that I may be frank with you, Mr. Holmes. You have the feelings of a gentleman. How quick a woman’s instinct is to find it out. I will treat you as a friend.”

“I cannot promise to reciprocate, madame. I am not the law, but I represent justice so far as my feeble powers go. I am ready to listen, and then I will tell you how I will act.”

“No doubt it was foolish of me to threaten a brave man like yourself.”