As I passed the table I noticed a half-sheet of note-paper lying on the blotter. My name was at the top of it and I snatched it up and read it.

“Dear Clayton,

“They have just driven up outside. Three of them. I am going with them if necessary because I daren’t give the game away by delaying them an hour. It’s 5.30 now. I’ll try to leave this where you will find it. They’re at the door now. Perhaps you can follow.

“Moore.”

Below his signature was another line, written so hastily that it looked hardly the same handwriting:

“Look at the wires!”

I slipped the note into my pocket and ran into his bedroom. The telephone was intact, but at the back of the clothes closet in which he kept it I found two wires evidently cut from the reel left over from the original installation, running up the wall and through a tiny hole in the ceiling. They were roughly joined to the two wires of our telephone.

Our line had been tapped!

I hesitated for a moment and read his note again. The appeal for help in that sentence, “Perhaps you can follow,” set me raging with anger and dismay. They had been playing with us all along, then. They knew all our plans. That was why they had come early probably. And now Moore was helpless in their hands.

The wires that tapped our line evidently ran into the empty flat above. So, in the faint hope of learning something further, I locked Moore’s door again and mounted the stairs with rising anxiety and anger. It is no pleasant thing at any time to realize that you have been played with as a mouse is played with by a cat. I firmly believed now that this same gang had been responsible for Margaret’s disappearance. And now Moore was in their hands and—possibly—Natalie. For it was no good blinking the facts. And they had been laughing at us—playing with us—all the while.

I never stopped to think whether the door of the vacant flat might be locked. I was prepared to break it down anyway, for I was past the stage of trying to keep up appearances and work in the dark, and I never stopped to wonder whether there might be other people in the house who would have something to say about what was going on—the young doctor, for instance.

Instead, I went up to the door and tried the handle cautiously. For there might be a watcher in there still. To my amazement, the door gave under my hand and swung open, and I stepped as silently as I could into a pitch-dark room.