“Supposing,” he said, “I decline to remain here? Supposing I say that, believing you now to have a guilty knowledge of this murder, I repudiate our bargain? Supposing I say that I will have nothing more to do with your thousand guineas,—that I will leave this house?”
“Then we come to close quarters,” the Prince answered, “and you force me to tell you in plain words that, until I am ready for you to leave it, you are as much a prisoner in this room as though the keys of the strongest fortress in Europe were turned upon you. I have told you this before. I thought that we perfectly understood one another.”
“I did not understand,” the doctor protested. “I knew that there was trouble, but I did not know that it was this!”
“The fact of your knowing or not knowing makes no difference,” the Prince answered. “You are no longer a free agent. The only question for you to decide is whether you remain here willingly or whether you will force me to remind you of our bargain.”
The doctor was sitting down again now. All the time he watched the Prince with a gleam in his eyes, partly of horror, partly of fear. He no longer doubted but that he was in the presence of a criminal.
“I am sorry,” the Prince continued, “that you have allowed this little matter to disturb you. I thought that we had arranged it all at our last interview. If you did not surmise my reasons for keeping you here, then I am afraid I gave you credit for more intelligence than you possess. You will excuse me now, I am sure,” he added, rising. “I have some letters to send off before I change. By the bye, do you care to give me your parole? It might, perhaps, lessen the inconvenience to which you are unfortunately subject.”
The doctor shook his head.
“No,” he said, “I will not give my parole!”
Late that night, he tried the handle of his door and found it open. The corridor outside was in thick darkness. He felt his way along by the wall. Suddenly, from behind, a pair of large soft hands gripped him by the throat. Slowly he was drawn back—almost strangled.
“Let me go!” he called out, struggling in vain to find a body upon which he could gain a grip.