Nayland Smith, who had been audibly counting the doors along the corridor as we passed them, seized the woman’s arm without ceremony, and pulled her into the apartment she had been on the point of quitting, closing the door behind us as we entered.

“Smith!” I began, “for Heaven’s sake what are you about?”

“You shall see, Petrie!” he snapped.

He released the woman’s arm, and pointing to an arm-chair near by—­

“Be seated,” he said sternly.

Speechless with amazement, I stood, with my back to the door, watching this singular scene.  Our captive, who wore a smart walking costume and whose appearance was indicative of elegance and culture, so far had uttered no word of protest, no cry.

Now, whilst Smith stood rigidly pointing to the chair, she seated herself with something very like composure and placed the leather bag upon the floor beside her.  The room in which I found myself was one of a suite almost identical with our own, but from what I had gathered in a hasty glance around, it bore no signs of recent tenancy.  The window was widely opened, and upon the floor lay a strange-looking contrivance apparently made of aluminum.  A large grip, open, stood beside it, and from this some portions of a black coat and other garments protruded.

“Now, madame,” said Nayland Smith, “will you be good enough to raise your veil?”

Silently, unprotestingly, the woman obeyed him, raising her gloved hands and lifting the veil from her face.

The features revealed were handsome in a hard fashion, but heavily made-up.  Our captive was younger than I had hitherto supposed; a blonde; her hair artificially reduced to the so-called Titian tint.  But, despite her youth, her eyes, with the blackened lashes, were full of a world weariness.  Now she smiled cynically.

“Are you satisfied,” she said, speaking unemotionally, “or,” holding up her wrists, “would you like to handcuff me?”

Nayland Smith, glancing from the open grip and the appliance beside it to the face of the speaker, began clicking his teeth together, whereby I knew him to be perplexed.  Then he stared across at me.

“You appear bemused, Petrie,” he said, with a certain irritation.  “Is this what mystifies you?”

Stooping, he picked up the metal contrivance, and almost savagely jerked open the top section.  It was a telescopic ladder, and more ingeniously designed than anything of the kind I had seen before.  There was a sort of clamp attached to the base, and two sharply pointed hooks at the top.

“For reaching windows on an upper floor,” snapped my friend, dropping the thing with a clatter upon the carpet.  “An American device which forms part of the equipment of the modern hotel thief!”

He seemed to be disappointed—­fiercely disappointed; and I found his attitude inexplicable.  He turned to the woman—­who sat regarding him with that fixed cynical smile.