"It came from that room," she whispered.

Again that low moan rent the stillness of the night.

The two listeners decided to put their original plan into action. Tuppence led the way to where she had seen the gardener put the ladder. Between them they carried it to the side of the house from which they had heard the moaning. All the blinds of the ground floor rooms were drawn, but this particular window upstairs was unshuttered.

Tommy put the ladder as noiselessly as possible against the side of the house.

"I'll go up," whispered Tuppence. "You stay below. I don't mind climbing ladders and you can steady it better than I could. And in case the doctor should come round the corner you'd be able to deal with him and I shouldn't."

Nimbly Tuppence swarmed up the ladder, and raised her head cautiously to look in at the window. Then she ducked it swiftly, but after a minute or two brought it very slowly up again. She stayed there for about five minutes. Then she descended again.

"It's her," she said breathlessly and ungrammatically, "But oh! Tommy, it's horrible. She's lying there in bed, moaning and turning to and fro-and just as I got there a woman dressed as a nurse came in. She bent over her and injected something in her arm and then went away again. What shall we do?"

"Is she conscious?"

"I think so. I'm almost sure she is. I fancy she may be strapped to the bed. I'm going up again, and if I can, I'm going to get into that room."

"I say, Tuppence-"

"If I'm in any sort of danger I'll yell for you. So long."

Avoiding further argument Tuppence hurried up the ladder again. Tommy saw her try the window, then noiselessly push up the sash. Another second, and she had disappeared inside.

And now an agonising time came for Tommy. He could hear nothing at first. Tuppence and Mrs. Leigh Gordon must be talking in whispers if they were talking at all. Presently he did hear a low murmur of voices and drew a breath of relief. But suddenly the voices stopped. Dead silence.

Tommy strained his ears. Nothing. What could they be doing?

Suddenly a hand fell on his shoulder.

"Come on," said Tuppence's voice out of the darkness.

"Tuppence! How did you get here?"

"Through the front door. Let's get out of this."

"Get out of this?"

"That's what I said."

"But-Mrs. Leigh Gordon?"

In a tone of indescribable bitterness Tuppence replied.

"Getting thin!"

Tommy looked at her, suspecting irony.

"What do you mean?"

"What I say. Getting thin. Slinkiness. Reduction of weight. Didn't you hear Stavansson say he hated fat women? In the two years he's been away, his Hermy has put on weight. Got a panic when she knew he was coming back, and rushed off to do this new treatment of Dr. Horriston's. It's injections of some sort, and he makes a deadly secret of it, and charges through the nose. I daresay he is a quack-but he's a damned successful one! Stavansson comes home a fortnight too soon when she's only beginning the treatment. Lady Susan has been sworn to secrecy, and plays up. And we come down here and make blithering idiots of ourselves!"

Tommy drew a deep breath.

"I believe, Watson," he said with dignity, "that there is a very good Concert at the Queen's Hall tomorrow. We shall be in plenty of time for it. And you will oblige me by not placing this case upon your records. It has absolutely no distinctive features."