The casket was empty!

It was like a conjuring trick.  That the hand had been in the box when I had taken it up from Adderley’s table I could have sworn before any jury.  When and by whom it had been removed was a puzzle beyond my powers of unravelling.  I stepped toward the telephone—­and then remembered that Paul Harley was out of London.  Vaguely wondering if Adderley had played me a particularly gruesome practical joke, I put the box on a sideboard and again contemplated the telephone doubtfully far a moment.  It was in my mind to ring him up.  Finally, taking all things into consideration, I determined that I would have nothing further to do with the man’s unsavoury and mysterious affairs.

It was in vain, however, that I endeavoured to dismiss the matter from my mind; and throughout the evening, which I spent at a theatre with some American friends, I found myself constantly thinking of Adderley and the ivory casket, of the mandarin of Johore Bahru, and of the mystery of the shrivelled yellow hand.

I had been back in my room about half an hour, I suppose, and it was long past midnight, when I was startled by a ringing of my telephone bell.  I took up the receiver, and: 

“Knox!  Knox!” came a choking cry.

“Yes, who is speaking?”

“It is I, Adderley.  For God’s sake come round to my place at once!”

His words were scarcely intelligible.  Undoubtedly he was in the grip of intense emotion.

“What do you mean?  What is the matter?”

“It is here, Knox, it is here!  It is knocking on the door!  Knocking!  Knocking!”

“You have been drinking,” I said sternly.  “Where is your man?”

“The cur has bolted.  He bolted the moment he heard that damned knocking.  I am all alone; I have no one else to appeal to.”  There came a choking sound, then:  “My God, Knox, it is getting in!  I can see. . . the shadow on the blind. . .”

Convinced that Adderley’s secret fears had driven him mad, I nevertheless felt called upon to attend to his urgent call, and without a moment’s delay I hurried around to St. James’s Street.  The liftman was not on duty, the lower hall was in darkness, but I raced up the stairs and found to my astonishment that Adderley’s door was wide open.

“Adderley!” I cried.  “Adderley!”

There was no reply, and without further ceremony I entered and searched the chambers.  They were empty.  Deeply mystified, I was about to go out again when there came a ring at the door-bell.  I walked to the door and a policeman was standing upon the landing.

“Good evening, sir,” he said, and then paused, staring at me curiously.

“Good evening, constable,” I replied.

“You are not the gentleman who ran out awhile ago,” he said, a note of suspicion coming into his voice.

I handed him my card and explained what had occurred, then: