A short time later they had left London behind them and were on their way to Paris and Zillah Mayhew. It was a fairly empty train and they had a first-class compartment to themselves. Grewgus proved himself a most entertaining companion, and told Lydon many interesting things in connection with himself and his profession, in the pursuit of which he took the keenest delight. He was about fifty-five, he told the young man, who was surprised at the statement, for, with his clean-shaven face and keen, alert expression, he looked a good ten years younger. He had been fifteen years at Scotland Yard, and ten years on his own. While at the Yard he had acquired a considerable experience of the underworld. He told him some wonderful stories of the wide ramifications of crookdom of all classes from the lowest to the most aristocratic, of high-class gangs directed by men who presented a most respectable appearance to the outside world, mixing in decent society, and adopting some well-known business or profession as a blind. He regaled him with some thrilling tales of how diamond had cut diamond, of the marvellous ingenuity with which certain professional detectives had got the better of their natural enemies, the criminals. Since he had been in private practice, his experiences had been less thrilling. He did a good deal in divorce business, and he was applied to in many cases of blackmail. “If this young woman turns out to be Elise Makris, as you suspect, we are likely to be up against a blackmailing gang here,” he observed. “And I should gather they pursue their activities chiefly abroad. You will remember the porter dropped the fact that Glenthorne was frequently out of England.” They snatched a light meal at Boulogne and they got out at Amiens for a very welcome whisky and soda. The Paris train was pretty full, and there was no opportunity for further disclosures of a confidential nature. Just before they rolled into the station, Grewgus whispered in his companion’s ear: “As you said I was to spare no expense, I sent a wire to an old ally of mine to meet the train. We have worked together very often, and he is a most useful fellow, being a splendid linguist. He can speak French like a native, even to its slang. It may be I shall have to watch more than one person, and he will come in handy for the other.” Evidently Mr. Grewgus was going to do the thing thoroughly, and the young man was pleased that he had got hold of such a painstaking fellow. The man with whom he had made the appointment was waiting on the platform, a clean-shaven, smart-looking individual rather like Grewgus himself. He was introduced to Lydon by the name of Simmons.