“That’s precisely what I will do,” declared Nick, starting up. “Look after this man, Mantell, till I return. I have a hunch that I shall not return alone.” Nick did not wait for a reply, but seized his hat and hurried from the office. He had noted the probable direction of the underground tube, and he hastened through the corridor and down the same back stairway over which Patsy had pursued Gaston Goulard. “Humph!” he ejaculated, upon arriving in the court. “It runs under these pavements and into the basement of this next building. I’ll find out who occupies it.” Nick hurried out to the side street and gazed up at the sign: “Acme Novelty Company.” “Novelty, indeed,” thought Nick, trying the door and finding it locked. “No one at home, eh? I’ll slip around and try the back door.” He had arrived nearly at the entrance to the alley, when he caught sight of a policeman on the opposite side of the street. He whistled and beckoned him over. “Come with me, Doyle, and have your gun within easy reach,” he said quietly. “Something up, Mr. Carter?” questioned Doyle, at once recognizing the detective. “Yes,” Nick nodded. “I don’t know yet, however, how big game we may find.” “Sure, I don’t care how big, sir.” “Follow me through the alley, then, and----” Nick stopped for an instant only. There had reached his ear a sound, though a bit muffled, which he instantly recognized--the sharp, spiteful crack of a revolver. “Come on, Doyle,” he snapped quickly. “That smacks of big game, all right. I reckon we’re in the nick of time.” Nick was running at top speed through the alley while speaking, with the burly policeman close on his heels. Ten seconds brought them to the back door of the building--which Patsy Garvan had left unlocked. Nick then heard the shouts of men within, and the furious voice of Gaston Goulard. “We’ve got them, Doyle,” he said quietly, pausing for an instant. “Are you ready?” “I’ll go ahead, if you say the word.” “Not much!” Nick turned the knob and threw open the door, shedding the bright daylight into the dim hall in which Goulard, Bart Bailey, Nolan, and Bolton were attempting with fierce threats to subdue Chick and Patsy, who had smashed the lamps in the subterranean chamber only a moment before. Nick broke in upon them with his revolver ready, shouting sternly: “Cut it, you fellows! Hands up, and----” His voice was drowned by the crack of a revolver in the hand of the only man who ventured any resistance--that of Bart Bailey. The rascal had crouched quickly back of Goulard, and had escaped Nick’s immediate notice. The bullet tore a hole in the detective’s sleeve and inflicted a slight wound in Doyle’s left shoulder. Goulard sprang aside instinctively. Bart Bailey was raising his weapon to fire again. Nick’s barked on the instant, and the bullet went true. Bailey pitched forward on his face in the narrow entry, dead before he hit the floor.