It was the signal that Bigman was waiting for. Bigman proceeded to follow the instructions Lucky had given him on board the Hilda when they were passing through the lock of Aphrodite's dome.

A blaster bolt shot out. It was at low intensity but its ionizing radiations produced the pungent odor of ozone in the air.

Matters remained so for a moment. All motion ceased. Morriss, his head against the overturned chair, made no move to get up. Bigman remained standing, like a small statue, with his blaster still held against his hip as though he had been frozen in the act of shooting.

And the target of the blaster bolt lay destroyed and in ruins upon the floor.

Lou Evans found his breath first, but it was only for a sharp exclamation, "What in space…"

Lyman Turner whispered, "What have you done?"

Morriss, panting from his recent effort, could say nothing, but he rolled his eyes mutely at Bigman.

Lucky said, "Nice shot, Bigman," and Bigman grinned.

And in a hundred fragments Lyman Turner's black computer case lay smashed and, for the most part, disintegrated.

Turner's voice rose. "My computer! You idiot! What have you done?"

Lucky said sternly, "Only what he had to do, Turner. Now, everyone quiet."

He turned to Morriss, helped that plump personage to his feet, and said, "All my apologies, Dr. Morriss, but I had to make certain that Turner's attention was completely misdirected. I had to use you for that purpose."

Morriss said, "You mean you don't suspect me of- of…"

"Not for one minute," said Lucky. "I never did."

Morriss moved away, his eyes hot and angry, "Then suppose you explain, Starr."

Lucky said, "Before this conference, I never dared tell anyone that I thought some man was benind the V-frogs. I couldn't even state it in my message to Earth. It seemed obvious to me that if I were to do so, the real enemy might be desperate enough to take some action-such as actually flooding one of the cities-and hold the possibility ol a repetition over the heads of all of us as blackmail. As long as he did not know that I went past the V-frog in my suspicions, I hoped he would hold off and play for time or, at most, try to kill only my friends and myself.

"At this conference I could speak of the matter because I believed the man in question to be present. However, I dared not take action against him without proper preparation for fear that he might place us under control despite the presence of the petroleum and for fear that his actions thereafter would be drastic. First I had to distract his attention thoroughly to make sure that, for a few seconds at least, he would be too absorbed in the surface activities of the group to detect, via his V-frog tools, the strong emotions that might be leaking out of Bigman's mind and mine. To be sure, there are no V-frogs in the building, but he might well be able to use the V-frogs in other parts of the city as he was able to use V-frogs out on the ocean's surface miles away from Aphrodite.

"To distract him then, I accused you, Dr. Morriss. I couldn't warn you in advance because I wanted your emotions to be authentic-and they were admirably so. Your attack on me was all that was needed."

Morriss withdrew a large handkerchief from a sleeve pocket and mopped his glistening forehead. "That was pretty drastic, Lucky, but I think I understand. Turner is the man, then?"

"He is," said Lucky.

Turner was on his knees, scrabbling among the fused and shattered shards of his instrument. He looked up with hate-filled eyes, "You've destroyed my computer."

"I doubt that it was a computer," said Lucky. "It was too inseparable a companion of yours. When I first met you, you had it with you. You stated you were using it to compute the strength of the inner barriers of the city against the threatened flood. Right now you have it with you presumably to help you if you should require new computations for your discussions with Dr. Morriss on the strength of those same inner barriers."

Lucky paused, then went on with a hard calmness in his voice. "But I came to see you in your apartment the morning after the threatened flood. I was merely planning to ask you some questions that involved no computing and you knew that. Yet you had your computer with you. You could not bring yourself to leave it in the next room. It had to be with you, at your feet. Why?"…

Turner said desperately. "It was my own construction. I was fond of it. I always carried it with me."

"I should judge it weighed some twenty-five pounds. Rather heavy, even for affection. Could it be that it was the device you used to maintain touch with the V-frogs at all tunes?"

"How do you intend to prove that?" flashed back Turner. "You said I myself was a victim. Everyone here is witness to that."

"Yes," said Lucky, "the man who, despite inexperience, so expertly barricaded himself at the dome lock, got his information from you. But was that information stolen from your mind or did you yourself donate it freely?"

Morriss said angrily, "Let me put the question directly, Lucky. Are you or are you not responsible for the epidemic of mental control, Turner?"

"Of course I'm not," cried Turner. "You can't do anything just on the say-so of a young fool who thinks he can make guesses and have them stick because he's on the Council."

Lucky said, "Tell me, Turner, do you remember that night when a man sat at one of the dome locks with a lever in his hand? Do you remember it well?"

"Quite well."

"Do you remember coming to me and telling me that if the locks were opened the inner transite barrier would not hold and that all of Aphrodite would be flooded? You were quite frightened. Almost panicky."

"All right. I was. I still am. It's something to be panicky about." He added, with his lip curling, "Unless you're the brave Lucky Starr."

Lucky ignored that. "Did you come to me with that information in order to add a little to the already existing confusion, to make sure that we were all disconcerted long enough for you to maneuver Lou Evans out of the city in order that he might be safely killed in the ocean? Evans was hard to handle, and he had learned too much concerning the V-frogs. Perhaps, also, you were trying to frighten me out of Aphrodite and off Venus."

Turner said, "This is all ridiculous. The inner barriers are inadequate. Ask Morriss. He's already seen my figures."

Morriss noded reluctantly. "I'm afraid Turner is right there."

"No matter," said Lucky. "Let's consider that settled. There was a real danger, and Turner was justifiably panicked… You are married, Turner."

Turner's eyes flicked uneasily to Lucky's face and away again. "So?"

"Your wife is pretty and considerably younger than yourself. You have been married for not quite a year."

"What is that intended to prove?"

"That you probably have a deep affection for her. Immediately after marriage you move into an expensive apartment to please her; you allow her to decorate it according to her tastes even though your own taste differs. Surely you wouldn't neglect her safety, would you?"

"I don't understand. What are you talking about?"

"I think you know. The one time I met your wife she told toe that she had slept through the entire excitement the night before. She seemed quite disappointed that she had. She also told me what a fine apartment house she lived in. She said it even possessed 'chambers.' Unfortunately, that meant nothing to me at the time, or I might have seen the truth then and there. It was only later, at the bottom of the ocean, that Lou Evans casually mentioned chambers and told me what they were. 'Chambers' is a word used on Venus to denote special shelters built to withstand the full force of the ocean in case a quake breaks a city dome. Now do you know what Fm talking about?"