Mrs. Marry delivered her startling piece of news with an air of triumph. She did not guess for one moment how very important it was, or in what peril it placed the Quiet Gentleman.

"He came back last night," she continued, "and he told me with his fingers how he had been lying ill in London town. Poor dear! he took it into his head to go for a jaunt, he says, and went by the night train. He meant to have come back to me next morning, but a nasty influenza took him and kept him away. I'm that glad he's come back I can't tell!" cried Mrs. Marry joyfully, "for he do pay most reg'lar, and gives not a bit of trouble, innocent babe that he is!" and having imparted her news, she hurried on down the lane.

The two men stood looking at one another.

"Brown back again!" said Alan. "Now we shall know the truth."

"If he knows it," said Blair dryly--he was less excited than his companion--"but I doubt if we shall learn much from him, Mr. Thorold. If he had anything to do with the murder, he would not have come back."

"But he must have something to do with it, man! Have you forgotten that it was he who stole the key of the vault from my desk?"

"No," said Blair pointedly, "nor have I forgotten that he did not use the key. It was Joe Brill who opened the vault."

"Indeed! And where did Joe get the key? Not from Mr. Phelps, for he still has his key. Ha!" cried Alan suddenly, "did Joe get it from Brown?"

"No, he did not. The key was not used at all. There was a third key in existence, of which neither you nor Mr. Phelps were aware. Marlow had had it made to provide against the contingency which arose. He had always resolved to feign death, should Lestrange track Mm. So he kept the third key, and Joe used it on that night."

"Well, even granting that such is the case, why should Brown have stolen my key? And how could he have known that it was in my desk?"

"I think we discussed that point before," replied the inspector composedly, "and that we came to the conclusion that Brown overheard your conversation with Mr. Phelps on the day of the funeral. Where are you going?"

"To see Brown. I am determined to get the truth out of him."

Blair looked at him.

"Well, Mr. Thorold," he said, "I don't suppose it will do any harm for you to see the man. Meanwhile I will go on to Mrs. Warrender's."

"But you ought to come with me and arrest him."

"I do not think I have sufficient evidence to procure a warrant, Mr. Thorold. A charge of murder is serious, you see."

"Pooh! pooh! I don't want him arrested for murder, but on the charge of breaking open my desk."

"I could do that certainly. Well, you go and see him, Mr. Thorold, while I interview Mrs. Warrender. I'll call along at the cottage later. You needn't let Brown out of your sight until I come."

"You'll arrest him?"

"If you wish it; I'll take the risk."

"Very good, I'm off!" and with an abrupt nod Alan ran down the lane. Blair looked after him with a queer smile on his dry face. He had his own ideas regarding the termination of Alan's attempt to make Brown the mysterious speak out.

Mrs. Warrender was at home when the inspector called. At first she felt she could not see him, for the idea of coming into contact with the police was abhorrent to her. She wondered if Blair could have discovered the relationship which existed between herself and Cicero, and it was her anxiety to ascertain this which made her grant the inspector an interview. If her brother were playing her false, the more she knew about his plans the better would she be able to frustrate them. Mrs. Warrender was a capable woman, and had a genius for intrigue. She was quite decided that she could hold her own even against the trained intelligence of a police officer.

And so it came about that the gentleman in question was shown into the drawing-room, a meretricious, gaudy apartment, which betrayed in furniture and decoration the tawdry taste of the doctor's widow.

She came forward to receive him in an elaborate tea-gown of pink silk trimmed with lace, and, in spite of the early hour, she wore a quantity of jewels. Blair had an eye for beauty, and could not deny that this lady was a fine woman, though, perhaps, too much of the ponderous type. He wondered why she did not wear mourning. She could have cared but little for her husband, he thought, to appear in gay colors so soon after his untimely end. But, in truth, Mrs. Warrender had never professed to be an affectionate wife. She had married for a home, and made no secret of it.

"Good-morning," she said, with a sharp glance at Blair's impassive face. "I understand that you belong to the police, and that you wish to see me--why, I cannot conceive."

"If you will permit me to explain myself, I will soon give you my reasons," said the inspector, in his best manner. "May I sit down? Thank you. Now we can talk at our ease."

"I suppose it is about the sad end of my poor husband," she said, in tones of grief, which her gay attire somewhat belied. "Have you found out the truth?"

"No; but I hope to do so--with your assistance."

She looked up suddenly.

"If you think I killed the poor lamb, you are mistaken," she said. "I can account for all my actions on that night, policeman."

This last was hurled at Blair with the object of keeping him well in mind of her condescension in receiving him.

"I never had the slightest suspicion of you," he protested. "My errand has to do with quite a different matter. And might I suggest," he added, a trifle testily, "that I am usually addressed as Inspector Blair?"

"Oh, of course, if you insist upon it!" she cried, with a shrug. "Inspector Blair--will that do?"

"That will do very well, thank you." He paused, and stared hard at the expensive tea-gown and the aggressive jewelry until the widow became restive. "Are you rich?" he asked abruptly.

"What has that got to do with you?" cried Mrs. Warrender furiously. "Remember you are tal............