“That settles it,” I breathed. “These were no ordinary thieves. This one stone was all they wanted.”

“But how did the fellow get in?”

“Through this door.”

“But it’s always locked.”

I shook my head. “It’s not locked now. See.” I pulled it open as I spoke.

As I did so something fluttered to the ground. I picked it up. It was a piece of silk, and the embroidery was unmistakable. It had been torn from a Chinaman’s robe.

“In his haste it caught in the door,” I explained. “Come, hurry. He cannot have gone far as yet.”

But in vain we hunted and searched. In the pitch darkness of the night, the thief had found it easy to make his getaway. We returned reluctantly, and Lord Yardly sent off one of the footmen posthaste to fetch the police.