It is Margaret’s eighteenth birthday anniversary, and her aunt goes to Tiffany’s for a costly cameo necklace as a birthday present for her charming niece. She is followed by the thief who owns the trained dog. Some hours after she has given Margaret the present, the thief goes back to Mrs. Knickerbocker’s house, engages the butler in conversation at the door, and allows the police dog to sneak into the house. Annie, the dog, has been trained to follow a person through the odor of personal belongings, and one of Margaret’s handkerchiefs, sniffed by the intelligent animal, is sufficient to take it to her boudoir. There it hides, awaiting her return. Margaret, after a busy and fatiguing day, consequent upon having so many friends call, goes to bed with the precious cameo necklace in its satin case clasped in her slender hands. Hardly has she sunk into slumber than a low whistle outside the house arouses Annie. She goes to the window. A few words from her master and Annie takes into her delicate jaws, without awakening the sleeper, the satin case. Then Annie jumps out of the window, takes the box to her master waiting nearby on Fifth Avenue, and he, having put the cameos in his pocket, throws the case into the gutter. It happens that Kid Joseph is nearby and he gets a glimpse of this man, but only a glimpse. In every outward sign it is Howard Dunbar, the Man of Mystery, and as Kid Joseph is hostile to Dunbar his hostility intensifies his certainty, that it is Dunbar. You can see the complications coming. Well, they come. But we are not going to spoil the excitement of your seeing the story unfolded by telling it to you now.