Reeder had made an appointment to see the bibulous agent at ten o’clock. The agent knew where certain photographs were to be obtained, and had promised to be waiting at the corner of St. Martin’s Lane at that hour. Mr. Reeder arrived as St. Martin’s Church clock was striking, but there was no sign of Billy Gurther. He had not appeared at half past ten, and Mr. Reeder decided to go to his house, for he was very anxious to complete his dossier. The landlady at Mr. Gurther’s lodgings had a surprising and disconcerting story to tell. Mr. Reeder had hardly left (she had witnessed his departure) before a messenger came, and Billy had gone out. He had returned in half-an-hour, very voluble and excited. He had been given a commission to collect cabaret turns in Spain. He had to leave London some time after nine, travel all night and catch the Sud Express in the morning. He was plentifully supplied with money. “He was so excited he was nearly sober,” said the uncharitable landlady. The sudden departure of an obscure music-hall agent, of whose existence he had been unaware until that afternoon, did not at all distress Mr. Reeder. It was the circumstances which attended his leaving, its rapidity, and, most important of all, the knowledge that was behind that sudden move, which made him alert and watchful. He might not be _persona grata_ at Scotland Yard, but little things like that did not trouble Mr. Reeder. He drove immediately to the big building on the Thames Embankment, sought, nay, demanded, an interview with the Chief Constable, who should have been at home and in bed, but was in fact in consultation with his five chiefs when the detective arrived. The first message sent to Mr. Reeder was cold and unpromising. Would he call in the morning? It was Gaylor who was detached from the conference to carry this message. “Go back to your chief, Mr. Gaylor,” said Reeder acidly, “and tell him I wish to see him this evening, at once. If I see him to-morrow it will be at the Home Office.” This was a threat: nobody knew it better than Gaylor. The exact extent and volume of Reeder’s power was not known. One thing was certain: he could be extremely unpleasant, and the consequences of his displeasure might even affect a man’s career. Gaylor returned instantly and summoned him to the conference, and there Mr. Reeder sat down and, quite uninvited, expounded a theory, and supported his fantastic ideas with a considerable amount of grimy literature. “We can stop Gurther at Southampton,” suggested Gaylor, but Reeder shook his head. “I think not. Let him soak into the Continent, and then we may pick him up without any trouble. Send a man to Southampton, and let him shadow him to Paris. In Paris he can blanket him.” Mason nodded. “If your theory is correct, there must be a method of proving it,” he said; “not a simple one perhaps----” “On the contrary, a very simple one,” said Mr. Reeder. He turned to Gaylor.