“He did not do anything so crude as to change once for all, suddenly, from Brotherhood to Davenant at a given point on his journey. He alternated between the two roles all along the line—I have always wondered what is the origin of that curious phrase ‘all along the line’; here I use it, you will understand, in a quite literal sense. Davenant got out at Paston Oatvile—the porter saw him. But, as we now know, it must have been Brotherhood who was travelling in the 4.50 from Paston Oatvile on. Yet it was as Davenant that he would have got out at Paston Whitchurch.” “How do you know that?” asked Reeves. “The ticket, of course. Brotherhood had a season, naturally, for he went up and down every day. At Paston Whitchurch, therefore, Brotherhood would have produced a season. It was Davenant who needed an ordinary single. The effect of all this was to create the simultaneous impression that both Brotherhood and Davenant came back to Paston Whitchurch that afternoon, and came by the same train. There was only one hitch in the plan, which could hardly have been foreseen. If Brotherhood happened to be murdered on the way, it would look very much as if Davenant had murdered him. And unfortunately he was murdered.” “Then you don’t think it was suicide?” asked Marryatt, with a catch in his voice. “If it was suicide, it was the result of a momentary insanity, almost incredibly sudden in its incidence. Suicide was certainly not part of the plan. A bogus suicide was, of course, a conceivable expedient; it would have been one way of getting rid of the undesirable Brotherhood’s existence. But consider what that means. It means getting hold of a substitute who looked exactly like Brotherhood—he could not foresee the excoriation of the features—and murdering him at unawares. It meant, further, that Davenant would be suspected of the murder. No plan could have been more difficult or more clumsy.” “Then you mean,” said Marryatt, “that we have to look for a murderer, somebody quite unknown to us?” “I didn’t say that,” replied Carmichael, with a curious look. “I mean that we have to look for a murderer, some one whom we have not hitherto suspected. If Davenant murdered Brotherhood, that was certainly suicide; for Davenant was Brotherhood. But that seems to me impossible. The evidence all goes to show that there was a very careful plot in contemplation, which was cut short by a quite unforeseen counterplot.” “But look here,” said Reeves, “if the original plan had come off, did he mean to come back here and live on here as Davenant?”