But for once even this time-tried detective found himself at fault. No marks were found on the old servant, nor could they discover in the rooms above any signs by which this one remaining occupant of the house could be directly associated with the crime which had taken place within it. Thereupon Mr. Gryce grew very thoughtful and entered upon another examination of the two rooms which to his mind held all the clews that would ever be given to this strange crime. The result was meagre, and he was just losing himself again in contemplation of the upturned face, whose fixed mouth and haunting expression told such a story of suffering and determination, when there came from the dim recesses above his head a cry, which, forming itself into two words, rang down with startling clearness in this most unexpected of appeals: "Remember Evelyn!" Remember Evelyn! Who was Evelyn? And to whom did this voice belong, in a house which had already been ransacked in vain for other occupants? It seemed to come from the roof, and, sure enough, when Mr. Gryce looked up he saw, swinging in a cage strung up nearly to the top of one of the windows I have mentioned, an English starling, which, in seeming recognition of the attention it had drawn upon itself, craned its neck as Mr. Gryce looked up, and shrieked again, with fiercer insistence than before: "Remember Evelyn!" It was the last uncanny touch in a series of uncanny experiences. With an odd sense of nightmare upon him, Mr. Gryce leaned forward on the study table in his effort to obtain a better view of this bird, when, without warning, the white light, which since his last contact with the electrical apparatus had spread itself through the room, changed again to green, and he realized that he had unintentionally pressed a button and thus brought into action another slide in the curious lamp over his head. Annoyed, for these changing hues offered a problem he was as yet too absorbed in other matters to make any attempt to solve, he left the vicinity of the table, and was about to leave the room when he heard Styles's voice rise from the adjoining antechamber, where Styles was keeping guard over the old butler: "Shall I let him go, Mr. Gryce? He seems very uneasy; not dangerous, you know, but anxious; as if he had forgotten something or recalled some unfulfilled duty." "Yes, let him go," was the detective's quick reply. "Only watch and follow him. Every movement he makes is of interest. Unconsciously he may be giving us invaluable clews." And he approached the door to note for himself what the man might do.