“Do you mean—” Mrs. Wilson began; but her husband was now in full flow, and he cut her short.
“What I mean is that the criminal deliberately laid the set of clues which pointed to the two men having murdered each other. We were bound to see through these, because the conclusion to which they pointed was just physically impossible. Then he laid the clues pointing to Walter Brooklyn, really meaning this time to get Walter Brooklyn hanged for the murders. My word, yes, this does throw a new light on the case. My dear, you’ve done it again. There’s lots to find out yet; but I’m sure it will come out right now that I know where to begin.”
“Then who was the murderer, dear? Have I told you somehow? I’m sure I don’t know who it was.”
“Neither do I, my dear. But I think I do know now how to begin looking for him. When I’ve found him I’ll tell you who he is. And half the credit of finding him will be yours.” The superintendent was so moved that he went up and kissed his wife as he kissed her only on occasions of rare exaltation. Then he got back to business with a sigh.
“If both sets of clues are false, my dear, you see that doesn’t make them valueless. They may still be used to point to the real murderer. Yes, I begin to see light already. If Walter Brooklyn did not send that telephone message, who did? Not much help there, I’m afraid, except that it was a very daring criminal indeed, and probably one who knew intimately both Walter Brooklyn and Liskeard House. Ringing up Brooklyn’s club shows that—he knew the man’s habits. There is something to go upon at all events. But there’s the walking-stick too—yes, that may be the point on which the whole case turns.”
By this time Superintendent Wilson was talking to himself, almost oblivious of his listener. His wife knew too well to interrupt him. She resumed her knitting, only looking up at him from time to time as he paced up and down the room.
“The stick. H’m. If Walter Brooklyn didn’t leave it in Prinsep’s room, who did? It was a very remarkable stick, and quite certain to be recognised. Just the thing, in fact, for a false clue. Let me see. Brooklyn said he lost it on the Tuesday afternoon—the day of the murders. That means that somehow or other the murderer got hold of it. H’m, h’m. We’re getting warm, my dear. When we know for certain who got hold of that stick we shall have found the murderer. Yes, we must certainly find out all about that stick. Left in a taxi, was it? I think not. I’m beginning to have a very shrewd idea of where it was left.” The superintendent paused.
“Where was it left, dear?”
“Wait till I know for certain, darling. I’ll find out, never fear. And then I shall know who the murderer was. But even then I shall be a long way off getting a conviction.” The superintendent laughed.
“But surely, if you know—”
“Knowing is one thing, and proving a case to a jury quite another. But that’s enough for the present. I want to sleep on this.” And with these words Superintendent Wilson went out into the garden to play with the children.
XXI
Don Quixote
While Fred Thomas was trying to make a shield for Walter Brooklyn’s guilt by throwing the suspicion upon others whom he himself believed to be innocent, Joan and Ellery were following up their attempt to prove her stepfather’s alibi. Two points they had already established, thanks to Ellery’s mingled sagacity and good fortune. Walter Brooklyn had definitely been in Leicester Square at a quarter to eleven, and in Piccadilly Circus at about twenty past eleven. So far his story was confirmed. Moreover, if he had been seen in the Circus at 11:20, it was difficult to believe that he had rung up his club from Prinsep’s room at Liskeard House, after making his way unseen into the building, less than ten minutes later. It was true that the evidence was not absolutely conclusive, as neither time could be fixed, quite certainly, to within a few minutes. But at least the evidence against him was severely shaken, and there seemed to be good reason for urging that the telephone message, round which the case had practically been built up, was a fake. Find out who sent it, the defence could argue, and you would find the real criminal.
Still, even if the telephone message could be discredited—and Ellery realised that this would take some doing—there remained the walking-stick, and the undoubted fact that Walter Brooklyn had expressed the intention of seeing Prinsep that evening. They could not feel that the evidence which they had so far gathered made his acquittal even probable, much less secure, especially as there was still no evidence that seemed to point in any other direction. Joan and Ellery felt that they must get further confirmation of the alibi. It was a question of accounting, not for a few minutes here and there, but for every minute of Walter Brooklyn’s time. Clearly, what now mattered most was where he had been between the time when the old night-watchman saw him in Piccadilly Circus and his return to his Club at about midnight. George Brooklyn had been seen alive as late as 11:30, and Prinsep only a few minutes before. If Walter Brooklyn had murdered either, it must have been done between 11:30 and midnight; for it seemed clear enough that he had not left his Club again during the night. Of this the night porter was positive. At the same time, it was desirable, though less important,
