“A noise in that room. Like sawing. Have you been there?”

Again Henry hesitated. “It’s locked,” he said.

“Where’s the detective? Shouldn’t you find him?”

“Come with me.”

So he was going to let her stay with him. She followed him across the landing. He paused at a door, bent down to listen. Then, very gingerly, he turned the handle and with his head motioned Roberta to come closer. She obeyed. Through the crack of the door came the sound of snoring, very deep and stertorous.

“Night nurse,” breathed Henry and closed the door.

“What are you going to do? Find the detective?”

“I’d like to find out for myself what she’s up to.”

“No, Henry. If anything’s wrong it would look so strange. Ssh!”

“What?”

“Look.”

A circle of light bobbed up the stairs and across the landing. “Damn!” whispered Henry. “He’s coming.”

He walked swiftly to the stairhead. “Hullo,” he said softly, “who’s that?”

“Just a minute, sir.”

The man came up quickly, flashing his torch on Henry. As he moved into the candlelight Roberta saw he wore a heavy overcoat and muffler and remembered that she herself was cold.

“What’s wrong here, sir?” asked the man. “Who’s been interfering with these lights? I said they were to be left on.”

Henry told him quickly that he had been awakened by a sound from the green drawing-room, and that he had seen Lady Wutherwood walk across the landing with a candle in her hand. “Miss Grey saw her too. Miss Grey came out soon after I did.”

“Where did she go, sir?”

“Upstairs.”

“You stay here, if you please, sir. Both of you. Don’t move.”

He threw his torch light on the upper stairs. They were half the width of the lower flight and steeper. The man ran lightly up and then disappeared. Roberta and Henry heard a door open and close, then another, and another. Then silence.

“Hell!” said Henry loudly, “I’m going…” Roberta snatched at his arm and he stopped short. Somewhere in the top floor of the house Lady Wutherwood screamed. Roberta knew at once it was she who screamed. It was the same note that had drilled through the silence of the lift well. It persisted for some seconds, intolerable and imbecilic, and then a door slammed it away into the background. Other voices sounded on the top floor. Somebody had joined them on the landing. It was the night nurse with her veil askew.

“Where’s she gone?” cried the night nurse. “I don’t accept the responsibility for this. Where’s she gone?”

On the top floor the man in the overcoat was saying: “Get back to your rooms, the lot of you. Move along now. Do what you’re told.” And a voice, Tinkerton’s: “I’m going to my lady.” “You’re doing what you’re told. Into your rooms, now, all of you. I’ll see you later.”

“You can’t lock me out.”

“I have locked you out. Stand aside, if you please.” The man in the overcoat came downstairs.