"Then you are one of the few people in London who do not," said Dr. Fall, with a smile. "One was an architect, the other a fairly efficient man of a type you will find on the continent of Europe, and who will be an electrician's assistant or a waiter with equal felicity. These men were engaged to assist in the construction of the house, they were brought from Italy with a number of other workmen, and entrusted with a section of its completion. Not satisfied with the handsome pay they received for their workmanship, they instituted a system of blackmail which culminated one night at Brakely Square in their untimely death." "Did Farrington kill them?" gasped Poltavo. "I will not go so far as to say that," said the suave secretary; "I only say that they died. Unfortunately for them, they were acting independently of one another and quarrelled violently when they found that they had both come upon a similar errand, having at last identified the mysterious gentleman, who had commissioned the house, with Gregory Farrington, a worthy and blackmailable millionaire." "So that was it," said Poltavo, thoughtfully. "What a fool I was not to understand, not to see the connection. They were shot dead outside Farrington's house. Who else could have committed the crime but he?" "Again, I will not go so far as to say that," repeated the secretary; "I merely remark that the men died a most untimely death, as a result of their eagerness to extract advantages from Mr. Farrington, which he was not prepared to offer. You, Count Poltavo, are in some danger of sharing the same fate." "I have been in tighter holes than this," smiled Poltavo, but he was uneasy. "Do not boast," said the doctor quietly. "I doubt very much whether in your life you have been in so tight a hole as you are in now. We are quite prepared to kill you; I tell you that much, because Mr. Farrington does not ordinarily take risks. In your case, however, he is prepared, just so long as you are impressed with his power to punish, to give you one chance of life. Whether you take that chance or not entirely depends upon yourself. He will not extract any oaths or promises or pledges of any kind; he will release you with the assurance that if you will serve him you will be handsomely rewarded, and if you fail him you will be most handsomely killed; do I make myself clear?" "Very," said Poltavo, and the hand that raised the cigarette to his lips trembled a little. "I would like to add," began the doctor, when the shrill sound of a ringing bell rang through the vaulted apartment. Fall sprang up, walked quietly to the wall, and placed his ear against a portion which appeared to be no different to any other, but which, as Poltavo gathered, concealed a hidden telephone. "Yes?" he asked. He listened. "Very good," he said. He turned to Poltavo, and surveyed him gravely.