With the other hand he removed the shawl and looked into a wan face seamed with want and dissipation. “You know Jack?” he said. “Heavens! Jack! Yes.” “Will you go up and see him?” She fell back, but the hand stayed her. “He did it, then?” she cried. “You saw some one, then?” “Yes; but for Heaven’s sake don’t mix me up in anything like murder.” Carter watched the nervous twitching of the woman’s lips and waited for her to calm herself. “When was he here?” he asked. “Last night.” “What was he like?” “He was rather tall, and had a step as stealthy as a tiger’s.” “You saw him come?” “Yes.” “And go?” “I did.” “How long was the man upstairs?” “Not over twenty minutes.” “Did you suspect a crime?” “I did; but I hadn’t the nerve to go up after he went away. I only guessed his mission.” Nick at last released the creature, who had in the meantime called herself Gutter Nan for identification, and went away. “It’s the second crime,” was all the remark he made to himself. The detective sent word to police headquarters, and as the crime, like the murder of Mother Flintstone, came too late for the morning papers, the afternoon journals got it. No one knew among the reporters that Jack Redmond had been Carter’s spy. None was told who was meant by “the master” in the sentence on the wall; they only guessed at that, and some queer guesses they made, too. Carter found Margie Marne that same day, and the girl’s first question was about his trail. “I’ve got a strange letter here,” said the girl, handing the detective a note she had just received. The detective drew it from the envelope and read as follows: “MISS MARNE: If you want to hear of something to your advantage please come to the Trocadero to-day at two and enter the first stall on the right. Come alone, for this is business of importance, and greatly concerns you. “BUSINESS.” After reading the message the detective looked up and found the eyes of the girl riveted upon his face. “Well?” he asked. “Shall I go?” “Yes.” “I’ll do anything you tell me to,” was the reply, and a faint smile flitted across the girl’s face. “Have you fears, Margie?” “Yes. I fear all the time ever since the death of Mother Flintstone.” “Who, think you, is ‘Business’?” “An enemy.” “Then, why go to the Trocadero?” “Because you say so.” Carter promised the girl that he would not be far off at the hour mentioned in the letter, and Margie agreed to be on hand. He did not see fit to tell her about Jack Redmond’s death, as it might unnerve her, and, bidding her good-by, he left the house. It was near two that afternoon when a man, who would not have been taken for Nick, entered the Trocadero on the Bowery, and seating himself at a table called for a drink. The place was not very well filled at the time, and while he sipped his wine the detective looked around the place.