ILLUSTRATED BY KRENKEL As one of the Guardian ships protecting Earth, the crew had a problem to solve. Just how do you protect a race from an enemy who can take over a man's mind without seeming effort or warning? "That hand didn't move, did it?" Edwardson asked, standing at the port, looking at the stars. "No," Morse said. He had been staring fixedly at the Attison Detector for over an hour. Now he blinked three times rapidly, and looked again. "Not a millimeter." "I don't think it moved either