Anaesthesia! But if that were so, it was useless to pursue the little man who now, having glanced once again into his notebook--a leaflet of instructions, no doubt--was moving stealthily down the corridor. One whiff of the substance and he, like the others, would--"But, no!" squealed Peter Pettigrew. For a thought had struck him with swift, encouraging force. Over his right shoulder was slung that which made him invulnerable to the spy's treacherous weapon. His gas mask! * * * * * To think, with this reborn Peter, was to act. In an instant he had whipped the mask from its sack and snuggled it about his face. Sucking filtered air through its _kobold_-like mouthpiece lent the final touch of isolation from worldliness--a process begun with the donning of the tinted spectacles. But protected, now, from fumes and glooms alike, hand resting on the comforting grip of his automatic, Peter crept down the staircase. The door through which the stranger had vanished was labelled POWDER ROOM: DANGER! in bold scarlet. As Peter drew nearer this door he was astonished to hear a faint muttering. Peering cautiously around the door-jamb he discovered this was the stranger murmuring petulantly to himself as he scowled at his little book. "It says," frowned the stocky man, "three more. But where in the name of Hypnos _are_ they? There's no one else in here. Another infernal mix-up in the O.D.D., that's what! I wish they'd get things straightened out--" Then Peter moved. Whipping his automatic out of its holster, he burst into the ammunition-packed room, shouting a wild and--he hoped--stern command. "Hands up!" he cried. "Surrender in the name of the--I mean, stick 'em up! I've got you!" The little man whirled, startled. But surprisingly, his lips cracked in a grin, and his voice was pleased. "Oh, _there_ you are!" he said. "I was worrying about you. The others coming along soon? Well--nighty-night!" And with a movement so swift, so deft, that no human eye could follow it, his hand dipped into the sack, grasped a handful of the slumber-producing dust--and flung it squarely into Peter's face! * * * * * For a moment, sheer shock immobilized Peter. He had expected cringing capitulation; he had met defiance, instead. It is a different matter to dream of slaughtering hundreds of charging enemies than to pull the trigger on one, small antagonist armed with only a gunnysack. So Peter did nothing. But the _saboteur_ did an amazing thing. He pencilled a checkmark in his little notebook. Then, quietly crooning a tune that sounded astonishingly like a lullaby, he shouldered his bag and started from the room. Peter roused. His piping voice rang clarion-clear in the echoing chamber. "Oh, no you don't! Stand still, you! Drop that bag and lift your hands or I'll--I'll--"