The way to the little cellar below the back office lay along a narrow passage, and this Mr. Martin followed, striking a fresh match as he went. Every detail came back to him, as though he had last passed this way yesterday, instead of fifteen years ago. The door of the little cellar closed with a spring; as he pushed it open the spring creaked with a note which he remembered so well, and the door closed behind him with the same muffled bang. Again he raised his match and looked around him anxiously. The cellar appeared to be the same as he had left it, even to a mildewed packing case against the wall, which had sometimes been used as a table. Only here, as in the larger cellar, the electricians had been at work. There was a lamp holder on the ceiling, but this time it held a lamp. It was evidently by the light of this lamp that Lacey had made his discovery. There was no reason why he should not use it too. The match had burnt down very near his fingers, but as he dropped it he caught sight of the switch. Without troubling to light another match he groped his way towards it and turned it on. There was a flash and a sharp report, but the cellar remained in complete darkness. Mr. Martin, with a gasp, leapt for the door in sudden panic. Someone hidden in the cellar must have fired at him. Then, after a moment, the absurdity of the idea forced itself upon him. The report had not been nearly loud enough for a pistol, and the cellar was far too small to conceal anybody. With a short laugh, but with trembling fingers, he felt for his matchbox and struck a light. Then at once he saw what had happened. The globe had burst as he turned on the current, and only the butt remained in the holder. He turned to look at the switch, and then for the first time he noticed that something white was hanging from it by a string. He bent down and held his match close to it. It was a white counter, bearing the figure IV in red ink. With a sudden access of fear he clutched at it, in order to examine it more closely. The string broke, and he stared at the counter in his hand, fascinated. He began to realize his position. He had been lured to this empty house, and the assassin was no doubt even now in the passage outside, waiting to plunge his deadly knife into him as he emerged. Thank heaven, he had brought his automatic with him! Mr. Martin was no coward. His plan of defence was quickly made. Throwing the match away, he took his stand on the far side of the cellar, facing the door, his automatic in his hand. If his assailant came in, he would hear the creak of the spring, and could fire before the man could reach him.