“I don’t know whether you will think my plan for killing Mark a clever one. Perhaps not. But if I do deserve any praise in the matter, I think I deserve it for the way I pulled myself together in the face of the unexpected catastrophe of your arrival. Yes, I got a window open, Mr. Gillingham, under your very nose; the right window too, you were kind enough to say. And the keys—yes, that was clever of you, but I think I was cleverer. I deceived you over the keys, Mr. Gillingham, as I learnt when I took the liberty of listening to a conversation on the bowling-green between you and your friend Beverley. Where was I? Ah, you must have a look for that secret passage, Mr. Gillingham. “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? “I don’t think that there is any more to tell you. This is a long letter, but then it is the last which I shall write. There was a time when I hoped that there might be a happy future for me, not at the Red House, not alone. Perhaps it was never more than an idle day-dream, for I am no more worthy of her than Mark was. But I could have made her happy, Mr. Gillingham. God, how I would have worked to make her happy! But now that is impossible. To offer her the hand of a murderer would be as bad as to offer her the hand of a drunkard. And Mark died for that. I saw her this morning. She was very sweet. It is a difficult world to understand. “Well, well, we are all gone now—the Abletts and the Cayleys. I wonder what old Grandfather Cayley thinks of it all. Perhaps it is as well that we have died out. Not that there was anything wrong with Sarah—except her temper. And she had the Ablett nose—you can’t do much with that. I’m glad she left no children. “Good-bye, Mr. Gillingham. I’m sorry that your stay with us was not of a pleasanter nature, but you understand the difficulties in which I was placed. Don’t let Bill think too badly of me. He is a good fellow; look after him. He will be surprised. The young are always surprised. And thank you for letting me end my own way. I expect you did sympathize a little, you know. We might have been friends in another world—you and I, and I and she. Tell her what you like. Everything or nothing. You will know what is best. Good-bye, Mr. Gillingham. “MATTHEW CAYLEY.