I had to make up my mind in a hurry. To tell the truth was out of the question. It was not only my own honour and safety that were at stake; there was another for whose sake my presence at that fatal dance must be concealed. I was on the point of denying all knowledge of the club when it struck me that I might be betrayed into some unconscious movement in going through the premises, or some thoughtless remark, which would reveal to a keen intelligence like Tarleton’s that I had been there before. I made an effort to seem as if I had been searching my memory. “Yes,” I said slowly, “now you speak of it I remember having been there. But I am not sure that I am free to say anything about it. My impression is that there was an implied pledge of secrecy. Everyone wore a mask and a disguise of some sort. It was supposed to be a place where people in very high positions could let themselves go in security. I was told there were sometimes judges present, and I rather think Cabinet Ministers, as well as peeresses, and so forth.” The specialist nodded gravely. “I expect the authorities knew what they were doing when they told Charles to call for me. We shall see whether he has found out who the man is that has been poisoned.” “He didn’t say it was a man,” I ventured to suggest. Sir Frank pursed his lips, but made no answer. He took out his gold repeater and began swinging it slowly, a sure sign that he was following out some train of thought. In another quarter of an hour the car drew up in one of the old-fashioned streets of Chelsea between King Street and the Fulham Road, at the entrance to the curious building or group of buildings that bore the name of Vincent Studios. The place resembled a rabbit warren. A short flight of steps led down from the street pavement into a dark, cavernous hall with doors opening out of it on three sides. Behind most of these doors were the studios of artists--one or two of them known to me--studios as cavernous if not as dark as the hall, and ending in glass doors that opened on mysterious gardens or garden yards overgrown with nasturtiums and other plants that seem to love the grime and cinders of suburban London. In the background one was aware of gray piles of timber, as of a mountain range closing a landscape. Some forgotten builder, perhaps, had died, leaving those stacks behind him, and his heirs had never discovered their existence, so that they had been left to the possession of the rats.