The bandit laughed again in a weird display of mirth. Something had changed the man, re-made him entirely, Mortenson thought. He was not the young, dashing desperado that had appeared in the laboratory ten days previously and walked away with the Fifth Dimensional apparatus! This man had a stubble of gray beard on his chin and his clothes were tattered and torn. And he seemed like a man who had gone through hell and left his soul with the devil's imps! "I said I'd come back, didn't I, professor?" he snapped savagely. "I thought you were telling me the truth, the night I cracked you on the head. But you're a liar, Mortenson!" "But ..." Mortenson began, stammering. "Shut up!" the bandit cut in with an oath. "You thought you could fool me, didn't you, Mortenson? But you didn't, you sneak! You never stopped to think that I'd have you watched, did you?" Mortenson winced. His vitals seemed to turn over within him at the cold chill of the killer's now sharp, biting voice. He was getting control of himself rapidly now and he stood in the middle of the floor like a graven image. He could not see the man's eyes, for they were hidden behind the vision cylinders of the helmet. But he could watch the fellow's lips. They were thick and cruel and curled up to the right side of his mouth with almost every word he spoke. "Then why didn't you kill me a week ago?" the scientist hissed suddenly. Again the bandit laughed. "I just wanted to see how far you'd go, Mortenson!" he snarled. "I thought I'd let you get your ten sets of apparatus built and then bump you off for your trouble!" "You're a cool liar!" said the scientist boldly. "There's something deeper than that. You thought you'd let me build ten more sets so you could take them for your pals, eh?" "You astound me with your psychic powers, professor!" the bandit sneered. "Of course I wanted the other sets! But I'm going to kill you nevertheless! Isn't it a disappointment to have worked like a dog merely to be killed in the end?" Mortenson was perfectly aware of that, but his deadly cold features failed to display the truth. He laughed loudly in the man's face. "You're not going to kill me or anybody else, my friend!" he said perhaps a trifle hysterically. "All I need to do is to call the guards!" "Humph!" the killer growled. "I fixed every bull on the place; knocked every one of them cold. They're a bunch of lazy flat-feet!" "Good Lord, man!" gasped Mortenson, sobering. "Don't tell me you killed all those detectives!" "No, I didn't kill 'em!" the other barked. "But it'll be a month before they get over their headaches! Now listen to me, Mortenson. You're a damned smart man ..." he lowered his voice, "and I hate to kill smart men...." "You don't say!" Mortenson cut in sarcastically. "Shut your mouth!" the bandit snarled, shoving forth his gun in a significant gesture. "I'll do the talking! You listen until I ask you to speak!"