He watched her himself, closely. The light was now very dim, but her face was still lit from the window behind him.

“They—may—have. I didn’t notice.”

“I understand Mr. Thoms complained of the delay. Perhaps he turned to see what you were doing?”

“He’s always watching— I beg your pardon; that’s got nothing to do with it.”

“What were you going to say?”

“Only that Mr. Thoms has rather an offensive trick of staring.”

“Did you happen to notice, before the operation, how much of the hyoscine solution there was in the bottle?”

She thought for some time.

“I think it was full,” she said.

“Has it been used since?”

“Once, I believe.”

“Good.”

He moved away from the window briskly, found the light switch and snapped it down. Jane rose to her feet. Her hands shook and her face was a little marked with tears.

“That’s all,” said Alleyn brightly. “Cheer up, Nurse Harden.”

“I’ll try.”

She hesitated a moment after he had opened the door, looked as if she wanted to say something further, but finally, without another word, left the room.

After she had gone Alleyn stood stockstill and stared at the opposite wall.

At last, catching sight of himself in an ornate mirror, he made a wry face at his own reflection.

“Oh, damn the doings,” said Alleyn.

CHAPTER TEN

Thoms in the Theatre

Tuesday, the sixteenth. Afternoon.

IT WAS MR. THOMS who took Alleyn into the theatre. After Jane left him the inspector had wandered into the hall and run into the plump little surgeon. Alleyn had explained who he was, and Thoms instantly assumed an expression of intense seriousness that made him look rather like a clown pulling a mock-tragic face.

“I say!” he exclaimed. “You’re not here about Sir Derek O’Callaghan’s business, are you?”

“That’s it, Mr. Thoms,” Alleyn rejoined wearily. “The man was murdered.”

Thoms began to babble excitedly. Alleyn held up a long hand.

“Hyoscine. At least a quarter of a grain. Wilful murder,” he said briefly.

“Lor’!” ejaculated Thoms.

“Lor’ it is. I’ve been badgering nurses and now I want to see the theatre of operations. It never struck me till just then what a localised implication that phrase has.”

“See the theatre?” said Thoms. “Yes. Of course. Look here. It’s not in use now. Sir John’s gone out. I’ll show you round if you like.”

“Thank you so much,” said Alleyn.

Thoms talked excitedly as he led the way. “It’s the most amazing thing I ever heard. Damn’ nasty business, too. I hope to God you don’t think I pumped hyoscine into the man. Thought you police chaps must have something up your sleeves when you pushed the inquest. Yes. Well, here we are. This is an anteroom to the theatre, where we wash and dress ourselves up for the business. Along there’s the anæsthetising-room. Here’s the theatre.”