"On the soft ground under the trees," he said, "I found his tracks right up to the point where--something happened. There were no other fresh tracks for several yards around. He was attacked as he stood close to the trunk of one of the elms. Six or seven feet away I found some other tracks, very much like this." He marked a series of dots upon the blotting-pad, for this conversation took place during the afternoon. "Claws!" I cried. "That eerie call! like the call of a nighthawk--is it some unknown species of--flying thing?" "We shall see, shortly; possibly to-night," was his reply. "Since, probably owing to the absence of any moon, a mistake was made"--his jaw hardened at the thought of poor Forsyth--"another attempt along the same lines will almost certainly follow--you know Fu-Manchu's system?" So in the darkness, expectant, we sat watching the group of nine elms. To-night the moon was come, raising her Aladdin's lamp up to the star world and summoning magic shadows into being. By midnight the high-road showed deserted, the common was a place of mystery; and save for the periodical passage of an electric car, in blazing modernity, this was a fit enough stage for an eerie drama. No notice of the tragedy had appeared in print; Nayland Smith was vested with powers to silence the Press. No detectives, no special constables, were posted. My friend was of opinion that the publicity which had been given to the deeds of Dr. Fu-Manchu in the past, together with the sometimes clumsy co-operation of the police, had contributed not a little to the Chinaman's success. "There is only one thing to fear," he jerked suddenly; "he may not be ready for another attempt to-night." "Why?" "Since he has only been in England for a short time, his menagerie of venomous things may be a limited one at present." Earlier in the evening there had been a brief but violent thunderstorm, with a tropical downpour of rain, and now clouds were scudding across the blue of the sky. Through a temporary rift in the veiling the crescent of the moon looked down upon us. It had a greenish tint, and it set me thinking of the filmed, green eyes of Fu-Manchu. The cloud passed and a lake of silver spread out to the edge of the coppice; where it terminated at a shadow bank. "There it is, Petrie!" hissed Nayland Smith. A lambent light was born in the darkness; it rose slowly, unsteadily, to a great height, and died. "It's under the trees, Smith!" But he was already making for the door. Over his shoulder: "Bring the pistol, Petrie!" he cried; "I have another. Give me at least twenty yards' start or no attempt may be made. But the instant I'm under the trees, join me." Out of the house we ran, and over on to the common, which latterly had been a pageant-ground for phantom warring. The light did not appear again; and as Smith plunged off toward the trees, I wondered if he knew what uncanny thing was hidden there. I more than suspected that he had solved the mystery.