"No," said Harding. "Frankly, I don't. Between Guest, Halliday, and Francis Billington-Smith, there isn'tt a penny to choose. They are all three of them strong suspects. Each one of them had a motive, large or small, and any one of them might be capable of committing murder. The fact that Billington-Smith was on the premises at eleven-thirty doesn't exonerate either of the other two; it only adds to the list of the people who might have murdered Sir Arthur. And the most important clue in my possession, that mysterious piece of paper, doesn't seem to have any bearing on any one of them. I am convinced, Sergeant, that if I can find out to whom that unfinished message refers I shall havc solved this case."
The Sergeant rubbed his chin. "You do set great store by that bit of writing, sir."
"Yes, in default of any other clue, I do. All the time I've been working on this case, trying to weigh the evidence of the principal suspects, I've again and again found myself brought up short by something unexplainable. In the case against Halliday, why were those papers thrown into the basket on top of that cheque? In the case against Guest, where the murder, if he did it, must have been thought out and performed in cold blood, the manner of it seems to be fantastic. In the case against Francis, if he was at the Grange as early as eleven-thirty, what kept him on the premises until after Halliday's interview with Sir Arthur? Why, if he had already robbed the safe, did he murder Sir Arthur?"
"When you put it like that, sir," said the Sergeant slowly, "it does look as though there's something in what you say. You mean you think we're on the wrong track altogether?"
"The case doesn't quite fit any of the people in it," said Harding. "I've had all along a feeling that I am missing something, and the conviction that it has to do with the message we found on the General's desk grew stronger with every statement I listened to."
"Have you got a theory about it, sir?" asked the Sergeant, interested.
"It's flattering it to call it a theory, Sergeant, but there is an idea in my head."
"Ah, a hunch, as you might say," nodded the Sergeant.
Harding laughed. "Yes, if you like. It seems to me a pretty far-fetched one, but I'm going to see if I can't follow it up. Where, exactly, is Mrs. Twining's house?"
The Sergeant's blank gaze focused on his face. "Mrs. Twining?" he repeated. "Could I take a look at that writing, sir?"