The word murmured almost inaudibly in Storm's throat. More mess! When he had heard the Apex summon to that room all the men who were in the house, he had naturally assumed that the order would be obeyed. With the only exit he knew ruled out, they were in the most ghastly blind alley two people could have strayed into. And once again the effect of his arrogant threatening was wearing off--more quickly than before, now that the men he was dealing with had grasped their own danger as well as the precariousness of his position. They would never let him get away if they could possibly prevent it, even though they ran the risk of being shot down in the attack. Each one of them would hope to be lucky and escape the few rounds Kit could loose off before they reached him, and each would be aware of the havoc which would be running amok once he got in touch with Scotland Yard. The Apex most of all. Surcon's hands were coming slowly down from his face, and a fiendish lustre burned in his pale blue eyes. His voice rang out suddenly, breaking in on the sizzling intensity of Storm's thought. "Wait, Captain Arden!" Surcon, too, could move like an arrow. And the shock of Susan's discovery had taken that last, infinitesimal perfection of keenness off Storm's alert brain--such an all but imperceptible blunting, yet great enough to make an incalculable difference. Ezra Surcon had flung up his hands and parted the hangings behind him. They saw that screwed to the wall was a small switchboard of porcelain from which protruded two six-inch levers of ebonite. And the Apex had one of these firmly gripped in each of his upraised hands. "Now listen to me," he shouted. "Haven't forgotten Piccadilly Circus, have you? Well, try to imagine twice that amount of NCl3 under--_Buckingham Palace_! Why else should I make my headquarters here? There's a tunnel from the cellars--or was, before the explosive was tamped in--and the Palace isn't far. The stuff's packed in huge blocks of ice, but when I pull down this switch it'll close a circuit, and this heat's a network of platinum wires among the charge. Shoot me, and the weight of my body'll pull down the switch. I'll prove to you I'm not bluffing, either. See the other switch? That connects with a tiny tube of nitrogen trichloride upstairs. Show you----" He dragged down the second lever. From over their heads came a dull, ear-numbing thud. The ceiling cracked, and little fragments of plaster broke away and crumbled to the floor.... The explosion, small as Surcon had said the charge was, shook the house. Came a hoarse exclamation outside the door, and someone barked out two words ... then, the muffled patter of feet stumbling up the stairs.... The Apex looked drawn and haggard suddenly, and an almost childlike puzzlement crept into his eyes. "What was that?"