Presently the manager appeared, middle aged, drowsy. "What can I do for you?" Luis laid the retrogression gun on the counter. "I'd like to know who this was sold to." The manager coughed. "Well, there are millions of them, hundreds of millions." "I know, but I have to find out." The manager picked it up. "It's a competitor's make," he said doubtfully. "Of course, as a courtesy to a customer...." He fingered it thoughtfully. "Do you really want to know? It's just a freezer. Not at all dangerous." Luis looked at it with concern. Just a freezer--not a retro gun at all! Then it couldn't have been the weapon used on him. Before he could take it back the manager broke it open. The drowsy expression vanished. "Why didn't you say so?" exclaimed the manager, examining it. "This gun has been illegally altered." He bent over the exposed circuits and then glanced up happily at Luis. "Come here, I'll show you." Luis followed him to the small workshop in the back of the store. The manager closed the door behind them and fumbled among the equipment. He mounted the gun securely in a frame and pressed a button which projected an image of the circuit onto a screen. The manager was enjoying himself. "Everybody's entitled to self-protection," he said. "That's why we sell so many like these. They're harmless, won't hurt a baby. Fully charged, they'll put a man out for half an hour, overload his nervous system. At the weakest, they'll still keep him out of action for ten minutes. Below that, they won't work at all." He looked up. "Are you sure you understand this?" It had been included in his re-education, but it didn't come readily to his mind. "Perhaps you'd better go over it for me." The manager wagged his head. "As I said, the freezer is legal, won't harm anyone. It'll stop a man or an elephant in his tracks, freeze him, but beyond that will leave him intact. When he comes out of it, he's just the same as before, nothing changed." He seized a pointer and adjusted the controls so as to enlarge the image on the screen. "However, a freezer can be converted to a retrogression gun, and that's illegal." He traced the connections with the pointer. "If this wire, instead of connecting as it does, is moved to here and here, the polarity is reversed. In addition, if these four wires are interchanged, the freezer becomes a retrogressor. As I said, it's illegal to do that." * * * * * The manager scrutinized the circuits closely and grunted in disgust. "Whoever converted this did a sloppy job. Here." He bent over the gun and began manipulating micro-instruments. He worked rapidly and surely. A moment later, he snapped the weapon together and straightened up, handing it to Luis. "There," he said proudly. "It's a much more effective retrogressor than it was. Uses less power too."