The drive that night, though it divided the drably commonplace from the wildly bizarre—­though it was the bridge between the ordinary and the outre—­has left no impression upon my mind.  Into the heart of a weird mystery the cab bore me; and in reviewing my memories of those days I wonder that the busy thoroughfares through which we passed did not display before my eyes signs and portents—­warnings.

It was not so.  I recall nothing of the route and little of import that passed between us (we both were strangely silent, I think) until we were come to our journey’s end.  Then: 

“What’s this?” muttered my friend hoarsely.

Constables were moving on a little crowd of curious idlers who pressed about the steps of Sir Crichton Davey’s house and sought to peer in at the open door.  Without waiting for the cab to draw up to the curb, Nayland Smith recklessly leaped out and I followed close at his heels.

“What has happened?” he demanded breathlessly of a constable.

The latter glanced at him doubtfully, but something in his voice and bearing commanded respect.

“Sir Crichton Davey has been killed, sir.”

Smith lurched back as though he had received a physical blow, and clutched my shoulder convulsively.  Beneath the heavy tan his face had blanched, and his eyes were set in a stare of horror.

“My God!” he whispered.  “I am too late!”

With clenched fists he turned and, pressing through the group of loungers, bounded up the steps.  In the hall a man who unmistakably was a Scotland Yard official stood talking to a footman.  Other members of the household were moving about, more or less aimlessly, and the chilly hand of King Fear had touched one and all, for, as they came and went, they glanced ever over their shoulders, as if each shadow cloaked a menace, and listened, as it seemed, for some sound which they dreaded to hear.  Smith strode up to the detective and showed him a card, upon glancing at which the Scotland Yard man said something in a low voice, and, nodding, touched his hat to Smith in a respectful manner.

A few brief questions and answers, and, in gloomy silence, we followed the detective up the heavily carpeted stair, along a corridor lined with pictures and busts, and into a large library.  A group of people were in this room, and one, in whom I recognized Chalmers Cleeve, of Harley Street, was bending over a motionless form stretched upon a couch.  Another door communicated with a small study, and through the opening I could see a man on all fours examining the carpet.  The uncomfortable sense of hush, the group about the physician, the bizarre figure crawling, beetle-like, across the inner room, and the grim hub, around which all this ominous activity turned, made up a scene that etched itself indelibly on my mind.

As we entered Dr. Cleeve straightened himself, frowning thoughtfully.

“Frankly, I do not care to venture any opinion at present regarding the immediate cause of death,” he said.  “Sir Crichton was addicted to cocaine, but there are indications which are not in accordance with cocaine-poisoning.  I fear that only a post-mortem can establish the facts—­if,” he added, “we ever arrive at them.  A most mysterious case!”