The young man from the west had arrived in New York only that afternoon, and his cousin, town born and bred, had already embarked upon the task of showing him the great city. They occupied a table in a somewhat insignificant corner of one of New York's most famous roof-garden restaurants. The place was crowded with diners. There were many notabilities to be pointed out. The town young man was very busy."See that bunch of girls on the right?" he asked. "They are all from the chorus in the new musical comedy-opens to-morrow. They've been rehearsing every day for a month. Some show it's going to be, too. I don't know whether I'll be able to get you a seat, but I'll try. I've had mine for a month. The fair girl who is leaning back, laughing, now, is Elsie Havers. She's the star.... You see the old fellow with the girl, just in a line behind? That's Dudley Worth, the multi-millionaire, and at the next table there is Mrs. Atkinson-you remember her divorce case?"It was all vastly interesting to the young man from the west, and he looked from table to table with ever-increasing interest."Say, it's fine to be here!" he declared. "We have this sort of thing back home, but we are only twelve stories up and there is nothing to look at. Makes you kind of giddy here to look past the people, down at the city."The New Yorker glanced almost indifferently at the one sight which to a stranger is perhaps the most impressive in the new world. Twenty-five stories below, the cable cars clanging and clashing their way through the narrowed streets seemed like little fire-flies, children's toys pulled by an invisible string of fire. Further afield, the flare of the city painted the murky sky. The line of the river scintillated with rising and falling stars. The tall buildings stabbed the blackness, fingers of fire. Here, midway to the clouds, was another world, a world of luxury, of brilliant toilettes, of light laughter, the popping of corks, the joy of living, with everywhere the vague perfume and flavour of femininity.The young man from the country touched his cousin's arm suddenly."Tell me," he enquired, "who is the man at a table by himself? The waiters speak to him as though he were a little god. Is he a millionaire, or a judge, or what?"The New Yorker turned his head. For the first time his own face showed some signs of interest. His voice dropped a little. He himself was impressed."You're in luck, Alfred," he declared. "That's the most interesting man in New York-one of the most interesting in the world. That's Sanford Quest.""Who's he?""You haven't heard of Sanford Quest?""Never in my life."The young man whose privilege it was to have been born and lived all his days in New York, drank half a glassful of wine and leaned back in his chair. Words, for a few moments, were an impossibility."Sanford Quest," he pronounced at last, "is the greatest master in criminology the world has ever known. He is a magician, a scientist, the Pierpont Morgan of his profession.""Say, do you mean that he is a detective?"The New Yorker steadied himself with an effort. Such ignorance was hard to realise-harder still to deal with.