"I think so," said the inspector, in a tone which was suggestive that he was very far from understanding. "I'll have everything typed out for you, and scale-plans of where you are to post your men. Above all, don't take anyone into your confidence." Inspector Wensdale nodded and looked across at Thompson, as if to assure himself that after all it really was not some huge joke. "If nothing happens on the 22nd, we shall carry-on the second, third, and fourth nights. In all probability we shall catch our man on the 23rd." "Then you know who it is?" spluttered the inspector in astonishment. "I hope to know on the 23rd," said Malcolm Sage dryly, as he rose and walked towards the door. Directness was his strong point. Taking the hint, Inspector Wensdale rose also and, with the air of a man not yet quite awake, passed out of the room. "You had better see him to-morrow, Thompson," said Malcolm Sage, "and explain exactly how the men are to be disposed. Make it clear that none must show themselves. If they actually see anyone in the act, they must track him, not try to take him." Thompson nodded his head comprehendingly. "Make it clear that they are there to watch; but I doubt if they'll see anything," he added. II At eleven o'clock on the night of July the 23rd, two motor lorries glided slowly along some three miles distant from one another. From their interiors silent forms dropped noiselessly on to the moon-white road. A moment later, slipping into the shadow of the hedge, they disappeared. All the previous night men had watched and waited; but nothing had happened. Now they were to try again. Overhead the moon was climbing the sky, struggling against masses of cloud that from time to time swung themselves across her disc. In the village of Hempdon all was quiet. The last light had been extinguished, the last dog had sent forth a final challenging bark, hoping that some neighbouring rival would answer and justify a volume of canine protest. On the western side of the highway, and well behind the houses, two figures were standing in the shadow cast by a large oak. Their faces and hands were blackened, rendering them indistinguishable from their surroundings. One wore a shade over a pair of gold-rimmed spectacles, a precaution against the moonlight being reflected on the lenses. Half an hour, an hour, an hour and a half passed. They waited. Presently one gripped the arm of the other and pointed. At the back of the house immediately-opposite there was a slight movement in the shade cast by a hedge. Then the line readjusted itself and the shadow vanished. A moment later it reappeared in a patch of moonlight, looking like a large dog. Stooping low Malcolm Sage and Thompson followed the dog-like form, themselves taking advantage of every patch of shadow and cover that offered.