Long after Alec’s not altogether willing departure, Roger sat smoking and thinking. On the whole, he was not sorry to be alone. Alec was proving a somewhat discouraging companion in this business. Evidently his heart was not in it; and for one so situated the ferreting out of facts and the general atmosphere of suspicion and distrust that is inevitably attendant on such a task, must be singularly distasteful. Roger could not blame Alec for his undisguised reluctance to see the thing through, but he also could not help thinking somewhat wistfully of the enthusiastic and worshipping prototypes whose mantle Alec was at first supposed to have inherited. Roger felt that he could have welcomed a little enthusiasm and worshipping at the end of this eventful and very strenuous day. He began to try to arrange methodically in his mind the data they had collected. First with regard to the murderer. He had made an effective escape from the house only, in all probability as it seemed, to enter it again by another way. Why? Either because he lived there, or because he wished to communicate with somebody who did. Which of these? Heaven only knew! He tried another line of attack. Which of the minor puzzles still remained unsolved? Chiefly, without doubt, the sudden change of attitude on the part of Mrs. Plant and Jefferson before lunch. But why need they have been apprehensive at all, if the murderer had been able to communicate with them after the crime had been committed? Perhaps the interview had been a hurried one, and he had forgotten to reassure them on some particularly vital point. Yet he had been able to do so in the course of the next morning. This meant that, up till lunch time at any rate, he had still been in the neighbourhood. More than that, actually on the premises, as it seemed. Did this point more definitely to the probability of his being one of the household? It seemed feasible; but who? Jefferson? Possibly, though there were several difficult points to get over if this were the case. The women were obviously out of the question. The butler? Again possibly; but why on earth should the man want to murder his master? Yet the butler was a strange figure, there was no getting away from that. And as far as Roger could judge, there had been no love lost between him and Stanworth. Yes, there was undoubtedly a mystery of some kind connected with that butler. Jefferson’s explanation of why Mr. Stanworth should have employed a prize-fighting butler did not strike one as quite satisfactory.