What deep philosophical remark Bates was going to make Masefield was not destined to hear, for at the same moment there was the sound of a sudden disturbance in the office beyond. The hoarse voice of a sergeant was heard demanding to know what this little game meant, there was a groan, and the collapse of a heavy body on the floor. Bates strode into the office.
"What is all this row about?" he demanded.
"It's Gregory, sir," the sergeant replied. "Went off half-an-hour ago on some special work for you, or so he said,and here's he back as drunk as a lord; regularly collapsed on the floor, he did. It's not the first time, either."
A sudden suspicion burst upon Masefield. He knelt by the side of the plain clothes man and felt his heart. There was a peculiar red mark round the man's neck as if something had been pulled very tightly round it.
"The man is no more drunk than I am," Jack said. "He has been attacked, and his breath is wholly free from any suspicion of drink. Look at that mark round his neck."
Very slowly the prostrate man struggled to a sitting position. When the fact had once been ascertained that there was no suggestion of intoxication, brandy was administered to him. He had a strange story to tell. He was carrying out instructions when suddenly somebody came behind him and placed a rope round his neck. Before he could recover himself he was partially strangled; he lost consciousness and lay on the pavement. When he came to himself again he was quite alone. He had managed to struggle back to the station, and once there had collapsed on the floor. Robbery was not the motive, for he had lost nothing.
"It's all part of the same mystery," Jack decided. "Something was going on behind that hoarding, and the criminals did not want the policeman to see. I shall walk back to my rooms that way. No, you had better not come along, inspector, in case you are spotted. I shall just walk very coolly by and keep my eye on that hoarding. Good-night!"
There was nothing more to be done, so Masefield was allowed to depart. He had ample food for thought as he walked along the deserted streets. He came at length to the great hoarding where the poster had stood. He stopped just for a moment, almost too amazed to move; then he forced himself to go forward again. For the striking Nostalgo poster was gone. It had been sawn neatly out of the boards of the hoardings leaving a blank square eye in its place!/p>