No one had heard a shot.
And yet there was the dead man, and there the revolver bullet, which had mushroomed out, as soft-nosed bullets will, and so inflicted a wound which must have caused instantaneous death.
Such were the circumstances of the Park Lane Mystery, which were further complicated by entire absence of motive, since, as I have said, young Adair was not known to have any enemy, and no attempt had been made to remove the money or valuables in the room.
All day I turned these facts over in my mind, endeavouring to hit upon some theory which could reconcile them all, and to find that line of least resistance which my poor friend had declared to be the starting-point of every investigation.
I confess that I made little progress.
In the evening I strolled across the Park, and found myself about six o'clock at the Oxford Street end of Park Lane.
A group of loafers upon the pavements, all staring up at a particular window, directed me to the house which I had come to see.
A tall, thin man with coloured glasses, whom I strongly suspected of being a plain-clothes detective, was pointing out some theory of his own, while the others crowded round to listen to what he said.
I got as near him as I could, but his observations seemed to me to be absurd, so I withdrew again in some disgust.
As I did so I struck against an elderly deformed man, who had been behind me, and I knocked down several books which he was carrying.