Ronald Adair was fond of cards-playing continually, but never for such stakes as would hurt him. He was a member of the Baldwin, the Cavendish, and the Bagatelle card clubs. It was shown that, after dinner on the day of his death, he had played a rubber of whist at the latter club. He had also played there in the afternoon. The evidence of those who had played with him - Mr. Murray, Sir John Hardy, and Colonel Moran - showed that the game was whist, and that there was a fairly equal fall of the cards. Adair might have lost five pounds, but not more. His fortune was a considerable one, and such a loss could not in any way affect him. He had played nearly every day at one club or other, but he was a cautious player, and usually rose a winner. It came out in evidence that, in partnership with Colonel Moran, he had actually won as much as four hundred and twenty pounds in a sitting, some weeks before, from Godfrey Milner and Lord Balmoral. So much for his recent history as it came out at the inquest.

On the evening of the crime, he returned from the club exactly at ten. His mother and sister were out spending the evening with a relation. The servant deposed that she heard him enter the front room on the second floor, generally used as his sitting-room. She had lit a fire there, and as it smoked she had opened the window. No sound was heard from the room until eleven-twenty, the hour of the return of Lady Maynooth and her daughter. Desiring to say good-night, she attempted to enter her son’s room. The door was locked on the inside, and no answer could be got to their cries and knocking. Help was obtained, and the door forced. The unfortunate young man was found lying near the table. His head had been horribly mutilated by an expanding revolver bullet, but no weapon of any sort was to be found in the room. On the table lay two banknotes for ten pounds each and seventeen pounds ten in silver and gold, the money arranged in little piles of varying amount. There were some figures also upon a sheet of paper, with the names of some club friends opposite to them, from which it was conjectured that before his death he was endeavouring to make out his losses or winnings at cards.

A minute examination of the circumstances served only to make the case more complex. In the first place, no reason could be given why the young man should have fastened the door upon the inside. There was the possibility that the murderer had done this, and had afterwards escaped by the window. The drop was at least twenty feet, however, and a bed of crocuses in full bloom lay beneath. Neither the flowers nor the earth showed any sign of having been disturbed, nor were there any marks upon the narrow strip of grass which separated the house from the road. Apparently, therefore, it was the young man himself who had fastened the door. But how did he come by his death? No one could have climbed up to the window without leaving traces. Suppose a man had fired through the window, he would indeed be a remarkable shot who could with a revolver inflict so deadly a wound. Again, Park Lane is a frequented thoroughfare; there is a cab stand within a hundred yards of the house. 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.