I was soon to play the part of a spy—a common policeman. I wonder what my leader at the bar would have said had he known! I was not altogether pleased with my duties, but I could not refuse Rouletabille the assistance he had begged me to give him. I took care not to make him see that I in the least objected, and for several reasons. I wanted to oblige him; I did not wish him to think me a coward; I was filled with curiosity; and it was too late for me to draw back, even had I determined to do so. That I had not had these scruples sooner was because my curiosity had quite got the better of me. I might also urge that I was helping to save the life of a woman, and even a lawyer may do that conscientiously. We returned along the gallery. On reaching the door of Mademoiselle Stangerson’s apartment, it opened from a push given by the steward who was waiting at the dinner-table. (Monsieur Stangerson had, for the last three days, dined with his daughter in the drawing-room on the first floor.) As the door remained open, we distinctly saw Mademoiselle Stangerson, taking advantage of the steward’s absence, and while her father was stooping to pick up something he had let fall, pour the contents of a phial into Monsieur Stangerson’s glass. Chapter XXI On the Watch The act, which staggered me, did not appear to affect Rouletabille much. We returned to his room and, without even referring to what we had seen, he gave me his final instructions for the night. First we were to go to dinner; after dinner, I was to take my stand in the dark closet and wait there as long as it was necessary—to look out for what might happen. “If you _see_ anything before I do,” he explained, “you must let me know. If the man gets into the ‘right’ gallery by any other way than the ‘off-turning’ gallery, you will see him before I shall, because you have a view along the whole length of the ‘right’ gallery, while I can only command a view of the ‘off-turning’ gallery. All you need do to let me know is to undo the cord holding the curtain of the ‘right’ gallery window, nearest to the dark closet. The curtain will fall of itself and immediately leave a square of shadow where previously there had been a square of light. To do this, you need but stretch your hand out of the closet, I shall understand your signal perfectly.” “And then?” “Then you will see me coming round the corner of the ‘off-turning’ gallery.” “What am I to do then?” “You will immediately come towards me, behind the man; but I shall already be upon him, and shall have seen his face.” I attempted a feeble smile. “Why do you smile? Well, you may smile while you have the chance, but I swear you’ll have no time for that a few hours from now.” “And if the man escapes?”