“The Varra live on life energy. When man conquered space, they foresaw danger to themselves. They are vulnerable, and if Earth suspected their motives, they’d be relentlessly destroyed. So—as I see it—they pretended to be friendly, and blamed the mind-vampirism on imaginary creatures living on Pluto. The Varra can communicate with us without the need for Helmets. They can kill too. But they seldom do that. Instead, pretending to protect space-travelers from the Plutonians, they drain a certain amount of life-energy from each person wearing a Helmet. We’re like cattle to them. We think they’re friendly, and so far we haven’t suspected the truth. As long as we didn’t suspect, the Varra were safe, and could keep on vampirizing us, without our knowledge. Once in a while a Varra badly in need of energy would drain too much, which would kill its host.” That was what had happened to Andrea. The Varra had tried to stop her from wrecking the _Maid’s_ radio, and—Duncan’s teeth showed. He went on telling his story, explaining what had happened. He made no excuses; there was no need for them now. Finally he said: “The Varra can be destroyed. And we can protect ourselves against them. That’ll be up to the scientists. If this ship gets through, it will mean that the Varra couldn’t stop me. I’ve got radium aboard. So I’ll put a Heaviside Layer around the cruiser—and blast off Sunward.” Duncan clicked the switch. No need to say more. Earth would understand, would believe. But now— He opened the port, after donning a suit and Helmet, and let the ship fill with the chlorine atmosphere. It would be better than oxygen, for his purposes. Iodine vapor would be even more effective, but he could not create that. If only he were a scientist, a technician, he could probably discover some other way of creating an artificial Heaviside Layer. But it didn’t matter. This way was surest and quickest, and there would be no machinery to fail him. Sealed within the ship once more, Duncan found the shipment of Martian radium, hi-jacked from the _Maid_, and removed it from its thick leaden container. He left it exposed, and went to the controls. The cruiser lifted from the surface of the plateau. It slanted up through the chlorine atmosphere, rockets bellowing. There was no need for split-second timing or unusual accuracy—within certain limits. He was heading Sunward. Nothing more was necessary. Except power— * * * * * The tubes thundered with ravening fury. The cruiser blasted up, acceleration jamming Duncan back into his seat. Then they were out of the air-envelope, in free space, controls locked. There was nothing more to do now but to drive on. The rockets would blast their fury into the void till the fuel was exhausted. Even then, the ship would speed on, into the tracks of commerce and the orbits of the inhabited planets. On the visiplate specks of light glimmered, resolving themselves into a nebulous cloud—the Varra.