The Secret Adversary by Agatha Christie

Impossible of course! Yet she almost went back to put the curtain aside and make sure….

Now they were entering the prison room. No place for anyone to hide here, thought Tuppence, with a sigh of relief, then chided herself indignantly. She must not give way to this foolish fancying–this curious insistent feeling that MR. BROWN WAS IN THE HOUSE…. Hark! what was that? A stealthy footstep on the stairs? There WAS some one in the house! Absurd! She was becoming hysterical.

Jane had gone straight to the picture of Marguerite. She unhooked it with a steady hand. The dust lay thick upon it, and festoons of cobwebs lay between it and the wall. Sir James handed her a pocket-knife, and she ripped away the brown paper from the back…. The advertisement page of a magazine fell out. Jane picked it up. Holding apart the frayed inner edges she extracted two thin sheets covered with writing!

No dummy this time! The real thing!

“We’ve got it,” said Tuppence. “At last….”

The moment was almost breathless in its emotion. Forgotten the faint creakings, the imagined noises of a minute ago. None of them had eyes for anything but what Jane held in her hand.

Sir James took it, and scrutinized it attentively.

“Yes,” he said quietly, “this is the ill-fated draft treaty!”

“We’ve succeeded,” said Tuppence. There was awe and an almost wondering unbelief in her voice.

Sir James echoed her words as he folded the paper carefully and put it away in his pocket-book, then he looked curiously round the dingy room.

“It was here that our young friend was confined for so long, was it not?” he said. “A truly sinister room. You notice the absence of windows, and the thickness of the close-fitting door. Whatever took place here would never be heard by the outside world.”

Tuppence shivered. His words woke a vague alarm in her. What if there WAS some one concealed in the house? Some one who might bar that door on them, and leave them to die like rats in a trap? Then she realized the absurdity of her thought. The house was surrounded by police who, if they failed to reappear, would not hesitate to break in and make a thorough search. She smiled at her own foolishness–then looked up with a start to find Sir James watching her. He gave her an emphatic little nod.

“Quite right, Miss Tuppence. You scent danger. So do I. So does Miss Finn.”

“Yes,” admitted Jane. “It’s absurd–but I can’t help it.”

Sir James nodded again.

“You feel–as we all feel–THE PRESENCE OF MR. BROWN. Yes”–as Tuppence made a movement–“not a doubt of it–MR. BROWN IS HERE….”

“In this house?”

“In this room…. You don’t understand? I AM MR. BROWN….”

Stupefied, unbelieving, they stared at him. The very lines of his face had changed. It was a different man who stood before them. He smiled a slow cruel smile.

“Neither of you will leave this room alive! You said just now we had succeeded. I have succeeded! The draft treaty is mine.” His smile grew wider as he looked at Tuppence. “Shall I tell you how it will be? Sooner or later the police will break in, and they will find three victims of Mr. Brown–three, not two, you understand, but fortunately the third will not be dead, only wounded, and will be able to describe the attack with a wealth of detail! The treaty? It is in the hands of Mr. Brown. So no one will think of searching the pockets of Sir James Peel Edgerton!”

He turned to Jane.

“You outwitted me. I make my acknowledgments. But you will not do it again.”

There was a faint sound behind him, but, intoxicated with success, he did not turn his head.

He slipped his hand into his pocket.

“Checkmate to the Young Adventurers,” he said, and slowly raised the big automatic.

But, even as he did so, he felt himself seized from behind in a grip of iron. The revolver was wrenched from his hand, and the voice of Julius Hersheimmer said drawlingly:

“I guess you’re caught redhanded with the goods upon you.”

The blood rushed to the K.C.’s face, but his self-control was marvellous, as he looked from one to the other of his two captors. He looked longest at Tommy.