But what am I saying? Did I deceive you at all? You have found out the secret⁠—that Robert was Mark⁠—and that is all that matters. How have you found out? I shall never know now. Where did I go wrong? Perhaps you have been deceiving me all the time. Perhaps you knew about the keys, about the window, even about the secret passage. You are a clever man, Mr. Gillingham.

I had Mark’s clothes on my hands. I might have left them in the passage, but the secret of the passage was now out. Miss Norris knew it. That was the weak point of my plan, perhaps, that Miss Norris had to know it. So I hid them in the pond, the Inspector having obligingly dragged it for me first. A couple of keys joined them, but I kept the revolver. Fortunate, wasn’t it, Mr. Gillingham?