I thought the matter over for a moment or two. The solution of the mystery certainly appealed to my dramatic sense.
"But," I said at last, "one wonders why the Carters took the trouble to arrange a scene of a supposed murder in the train: they might quite well have been caught in the act, and in any case it was an additional unnecessary risk. John Carter might quite well have been content to shed his role of Russian Prince, without such an elaborate setting."
"Well," he admitted, "in some ways you are right there, but it is always difficult to gauge accurately the mentality of a clever scoundrel. In this case I don't suppose that the Carters had quite made up their minds about what they would do when they left London, but that the plan was in their heads is proved by the hat, pince-nez, and railway ticket which they took with them when they started, and which, if you remember, were found on the line: but it was probably only because the train was comparatively empty, and they had both time and opportunity in the non-stop train, that they decided to carry their clever comedy through.
"Then think what an immense advantage in their future plans would be the Smithsons' belief in the death of their Prince. Probably Louisa would never have dreamed of marrying if she thought her aristocratic lover was an impostor and still alive: she would never have let the matter rest; her mind would for ever have been busy with trying to trace him, and bring him back, repentant, to her feet. You know what women are when they are in love with that type of scoundrel, they cling to them with the tenacity of a leech. But once she believed the man to be dead, Louisa Smithson gradually got over her grief and Henry Carter wooed and won her on the rebound. She was poor now, and her friends had quickly enough deserted her: she was touched by the fidelity of her simple lover, and he thus consolidated his position and made the future secure.
"Anyway," the Old Man in the Corner concluded, "I believe that it was with a view to making a future marriage possible between Louisa and Henry that the two brothers organised the supposed murder. Probably if the train had been full and they had seen danger in the undertaking they would not have done it. But the mise en scène was easily enough set and it certainly was an additional safeguard. Now in another week or so Louisa Smithson will be Henry Carter's wife, and presently you will find that John in London, and Henry and his wife, will be quite comfortably off. And after that, whatever suspicions Mrs. Smithson may have of the truth, her lips would have to remain sealed. She could not very well prosecute her only child's husband.
"And so the matter will always remain a mystery to the public: but the police know more than they are able to admit because they have no proof.
"And now they never will have. But as to the murder in the train, well!—the murdered man never existed."