l we find the key to the riddle
here, I wonder?"

Inspector Weymouth, who had concluded, I think, that the mysterious
telephone call was due to mental aberration on the part of Norris West,
was gnawing at his mustache impatiently when his assistant returned. I
administered the powerful restorative, and although, as later
transpired, chloral was not responsible for West's condition, the
antidote operated successfully.

Norris West struggled into a sitting position, and looked about him
with haggard eyes.

"The Chinamen! The Chinamen!" he muttered.

He sprang to his feet, glaring wildly at Smith and me, reeled, and
almost fell.

"It is all right," I said, supporting him. "I'm a doctor. You have
been unwell."

"Have the police come?" he burst out. "The safe--try the safe!"

"It's all right," said Inspector Weymouth. "The safe is locked--unless
someone else knows the combination, there's nothing to worry about."

"No one else knows it," said West, and staggered unsteadily to the
safe. Clearly his mind was in a dazed condition, but, setting his jaw
with a curious expression of grim determination, he collected his
thoughts and opened the safe.

He bent down, looking in.

In some way the knowledge came to me that the curtain was about to rise
on a new and surprising act in the Fu-Manchu drama.

"God!" he whispered--we could scarcely hear him--"the plans are gone!"

CHAPTER XIX

I HAVE never seen a man quite so surprised as Inspector Weymouth.

"This is absolutely incredible!" he said. "There's only one door to
your chambers. We found it bolted from the inside."

"Yes," groaned West, pressing his hand to his forehead. "I bolted it
myself at eleven o'clock, when I came in."

"No human being could climb up or down to your windows. The plans of
the aero-torpedo were inside a safe."

"I put them there myself," said West, "on returning from the War
Office, and I had occasion to consult them after I had come in and
bolted the door. I returned them to the safe and locked it. That it
was still locked you saw for yourselves, and no one else in the world
knows the combination."

"But the plans have gone," said Weymouth. "It's magic! How was it
done? What happened last night, sir? What did you mean when you rang
us up?"

Smith during this colloquy was pacing rapidly up and down the room. He
turned abruptly to the aviator.

"Every fact you can remember, Mr. West, please," he said tersely;