"We are always in the thick of it," replied Smith. "Our danger is no greater in Norfolk than in London. But what do they want to do? That man in the train with the case of instruments--WHAT instruments? Then the apparition of the green eyes to-night. Can they have been the eyes of Fu-Manchu? Is some peculiarly unique outrage contemplated--something calling for the presence of the master?" "He may have to prevent Eltham's leaving England without killing him." "Quite so. He probably has instructions to be merciful. But God help the victim of Chinese mercy!" I went to my own room then. But I did not even undress, refilling my pipe and seating myself at the open window. Having looked upon the awful Chinese doctor, the memory of his face, with its filmed green eyes, could never leave me. The idea that he might be near at that moment was a poor narcotic. The howling and baying of the mastiff was almost continuous. When all else in Redmoat was still the dog's mournful note yet rose on the night with something menacing in it. I sat looking out across the sloping turf to where the shrubbery showed as a black island in a green sea. The moon swam in a cloudless sky, and the air was warm and fragrant with country scents. It was in the shrubbery that Denby's collie had met his mysterious death--that the thing seen by Miss Eltham had disappeared. What uncanny secret did it hold? Caesar became silent. As the stopping of a clock will sometimes awaken a sleeper, the abrupt cessation of that distant howling, to which I had grown accustomed, now recalled me from a world of gloomy imaginings. I glanced at my watch in the moonlight. It was twelve minutes past midnight. As I replaced it the dog suddenly burst out afresh, but now in a tone of sheer anger. He was alternately howling and snarling in a way that sounded new to me. The crashes, as he leapt to the end of his chain, shook the building in which he was confined. It was as I stood up to lean from the window and commanded a view of the corner of the house that he broke loose. With a hoarse bay he took that decisive leap, and I heard his heavy body fall against the wooden wall. There followed a strange, guttural cry . . . and the growling of the dog died away at the rear of the house. He was out! But that guttural note had not come from the throat of a dog. Of what was he in pursuit? At which point his mysterious quarry entered the shrubbery I do not know. I only know that I saw absolutely nothing, until Caesar's lithe shape was streaked across the lawn, and the great creature went crashing into the undergrowth. Then a faint sound above and to my right told me that I was not the only spectator of the scene. I leaned farther from the window. "Is that you, Miss Eltham?" I asked. "Oh, Dr. Petrie!" she said. "I am so glad you are awake. Can we do nothing to help? Caesar will be killed." "Did you see what he went after?" "No," she called back, and drew her breath sharply.