One of these establishments he believed to be the resort of Continental gamblers driven from Soho by the too marked attentions of the police. The other was a place of even more questionable repute, and in both instances he had utterly failed to obtain the slightest information from the servants, who apparently "stood in" with the management. The third dwelling which courted observation was a flat situated above some business premises in another quiet street. So far as he could learn, it was tenanted by an elderly lady who was a helpless invalid, waited on by a somewhat curious couple. "They are Italians, I think," wrote the ex-policeman, "and very uncommunicative people. I have twice called, on one pretext or another, but when the door is opened it is always kept on the chain, and I cannot see more than the face of a man or woman and a few inches of wall beyond. Still, I have no reason to doubt that the view taken by the milkman and baker is correct, namely, that the owner of the flat is confined to her bed and is suffering from a nervous disease, which renders it imperative she should be shut off from all noise. The landlord informs me that these people have occupied the place for nearly two months. Their rent is paid in advance, and they have not given the slightest cause for complaint. There are, of course, in this district a large number of private hotels and lodging-houses, but they seem to be run on regular lines, and, although some of their patrons might well demand closer observation, I have come across nothing suggestive of any suspicious circumstance whatever with reference to them. I have detained my report until I was able to give details concerning the other houses in the district, and I will now fall back on the second part of your instructions, i.e., to maintain a close watch on the three establishments which I have picked out as being more unusual in their habits than the others." This was all. Brett read the concluding portion of the report to Fairholme. "He is a level-headed, shrewd observer," he said--"one of the few men whom I can trust to do exactly what I want, neither more nor less. I think when we return to London we must endeavour to get that chain taken off the invalid lady's door, or, at any rate, obtain some specific facts concerning her disease from her medical adviser." Fairholme smiled. "I am glad to hear," he cried, "that you do anticipate our return." "Oh," said Brett airily, "I never count on failure." Soon after three o'clock a report arrived from the agent in the Rue du Chaussée d'Antin. It read-- "Nothing unusual has occurred in the vicinity of the Cabaret Noir. The customers frequenting the place are all of the ordinary type and do not call for special comment.