certain that she had heard his voice. But then Bill had said that it was a very characteristic voice—an easy voice, therefore, to imitate. If Bill could imitate it so successfully, why not Cayley?
But perhaps it had not been such a cold-blooded killing, after all. Suppose Cayley had had a quarrel with his cousin that afternoon over the girl whom they were both wooing. Suppose Cayley had killed Mark, either purposely, in sudden passion, or accidentally, meaning only to knock him down. Suppose that this had happened in the passage, say about two o'clock, either because Cayley had deliberately led him there, or because Mark had casually suggested a visit to it. (One could imagine Mark continually gloating over that secret passage.) Suppose Cayley there, with the body at his feet, feeling already the rope round his neck; his mind darting this way and that in frantic search for a way of escape; and suppose that suddenly and irrelevantly he remembers that Robert is coming to the house at three o'clock that afternoon—automatically he looks at his watch—in half an hour's time.... In half an hour's time. He must think of something quickly, quickly. Shall he bury the body in the passage and let it be thought that Mark ran away, frightened at the mere thought of his brother's arrival? But there was the evidence of the breakfast table. Mark had seemed annoyed at this resurrection of the black sheep, but certainly not frightened. No; that was much too thin a story.
