But no such theories seemed tenable in this instance. Monkton's life, in the opinion of all who knew him, had been a well-ordered and blameless one. He had been a devoted husband; and he was a devoted father, wrapped up in his charming daughter, the sole legacy of that happy marriage. In the case of such a man, with so stainless a record, it was unthinkable that anything could leap to light from the past which could shame him to such an extent that he would, of his own act, abandon his office, and isolate himself from his child. Even granting such an hypothesis for a moment, and brushing aside all the evidences of his past life and all the knowledge of him gained through years by his relatives and intimate friends, how did such a theory fit in with the appearance on the scene of the stranger now dead? "You fear the worst?" queried Wingate one day, as Smeaton sat with him in his cosy rooms in Half Moon Street. "It is too early yet to give a decided opinion, if, in a case of such complexity, one could ever give a decided opinion at all," was the detective's answer. "But at present things point that way. What was the motive underlying the scheme? You can give the answer quickly--that all inquiries as to the real man are being stifled." "In other words, that Mr Monkton has been done away with, for motives we do not know, by the person or persons who put the man into the taxi?" Smeaton nodded. "That's what it seems to be at the moment, Mr Wingate. But we should be poor detectives if we pinned ourselves to any one theory, especially on such evidence--or rather want of evidence--as we have got at present. Cases as mysterious as this--and there was never one more mysterious--have been solved by unexpected means. If we can get hold of that driver who brought the dying man to Chesterfield Street, we may light upon something useful." "If he was an accomplice, as seems possible, he will never turn up," said Wingate gloomily. "Accomplice or not, I think the reward will tempt him," replied Smeaton, "even if he has to make up his tale before he comes. I expected he would come forward before now. But one of two things may have happened. Either he may be cogitating over what he shall say when he does come, or he may be an ignorant sort of fellow, who hardly ever reads the newspapers." "Anyway," resumed Smeaton, after a thoughtful pause, "if and when he does turn up, we shall know, with our long experience, what sort of a customer he is. You may rely upon it that if there is anything to be got out of him, we shall get it, whether it proves valuable or not." It was not a very cheering interview, certainly, but how could there be any chance of hopefulness at present? During the few days, however, the police had not been idle. They had made a few discoveries, although they were of a nature to intensify rather than tend to a solution of the mystery. They had established one most important fact.