Robert Moore Williams

The planet's natives were so similar to their conquerors that no one could tell them apart—except for their difference in thinking.

This was Graduation Day. The senior class from the Star Institute of Advanced Science was scheduled to go through the Museum of the Conquered and observe the remnants of the race that had once ruled this planet. There were many such museums maintained for the purpose of allowing the people to see the greatness their ancestors had displayed in conquering this world and also to demonstrate how thorough and how complete that conquest had been. Perhaps the museums had other reasons for existing, but the authorities did not reveal these reasons. Visiting such a museum was part of the exercises of every graduating class.

Billy Kasker arrived early, to take care of all last minute problems for Mr. Phipper, the instructor who would take the group through the museum, and to make certain that all of the members of the graduating class knew what they were supposed to do on the trip. Billy Kasker was class president. A handsome, husky youth, accommodating, generous, and thoughtful to a fault. He was well liked both by the faculty and the students. He was pleasant to everybody, even to Joe Buckner, who called him "teacher's pet" and sneeringly remarked that he had been elected class president as a result of a superb job of boot-licking.

Even such remarks as these had not disturbed Bill Kasker. He still acted as if Joe Buckner was his best friend.

"Are we all here, Billy?" the instructor called.

"All here, sir," Billy Kasker answered.

"Very well. Let's start to the museum. As we go through you may ask any questions you wish. However, I must insist you stay close to me and not wander from the group. We will be in no danger, you understand—the creatures living in the museum have had their fangs pulled most effectively—but even so we must not take chances."

The instructor led off. He was a fussy little person in a shiny black coat and a soft hat that was too big for him. No matter how much paper he stuffed inside the brim, the hat never seemed to fit right. Peering through glasses that were always threatening to fall off, he moved away from the Star Institute toward the nearby museum. The class of eight girls and nine boys followed him.

"Why do we have to go through this old museum?" Joe Buckner complained. "We already know everything about it."

"It's the rule," Billy Kasker answered. "The faculty thinks we should see the situation at first hand. Then we will have a better understanding of it."

Joe Buckner grunted disdainfully. "You're always sucking in with the big shots and telling everybody what they say."

"You asked me. I tried to tell you." Billy Kasker's voice was still pleasant. If a slight glint appeared in his eyes, it remained there for only a second.

The museum was an open area many miles long. It was enclosed by a high, electrically charged fence along which guard towers were placed at regular intervals. There was only one gate, to which the instructor led the class. A captain, resplendent in a brilliant uniform, came out of the guard house to greet them.

"The graduating class from the Star Institute, eh? Good. We had notice that you were coming. Guard, bring Mr. Phipper a Thor gun, then open the gates." The last was spoken in a brisk tone to the guard who had followed the captain.

The Thor gun was brought immediately. It was a small weapon, with a belt and holster. The captain took it from the holster. Watching, Billy Kasker had the impression that the weapon was made of glittering, spun glass. It had a short, heavy barrel in which tiny instruments were visible. Billy Kasker watched very closely.

"Do you know how to use it?" the captain asked.

"Oh, yes," the instructor answered.

"Is it so dangerous in there that we need a Thor gun?" Susan Sidwell said. Susan had majored in ionic chemistry and had graduated with high honors.

"No, it isn't dangerous at all," the instructor answered hastily. "The weapon is worn merely for the sake of tradition."

"No danger at all, young lady," the captain said. "Nothing to worry about. Not while you've got this, anyhow." He patted the Thor gun which the instructor was buckling to his waist.

The gates were open. The instructor in the lead, the group passed through. Billy Kasker brought up the rear. Joe Buckner was directly ahead of him.

They went first to see the wreckage of the city—shattered walls, tumbled buildings, streets with rubble still piled in them. Weeds and creeping vines grew over the broken bones of this city as if they were attempting to hide the ugly scars.

The instructor adjusted his voice to the proper tone. He had made this same speech to many graduating classes and he knew exactly what he was going to say.

"You understand, of course, that this part of the old city was almost completely destroyed in our attack of the year 4021 After Yevbro, or the year 1967, according to the way the natives reckoned time on this planet. This part of it has been allowed to remain the way our ships left it, as an example of the effectiveness of our weapons."

His voice gave the impression that he was personally participating in that attack and was enjoying the destruction that had taken place. He stood straight, squared his shoulders and breathed deeply.

"What happened to the natives who lived here?" Billy Kasker asked.

The instructor frowned. "Oh, they were killed." At first he was a little irritated at the question, then again satisfaction came back into his voice.

"They got what was coming to them for trying to resist our sky ships," Joe Buckner said.

"Oh, yes, they deserved their fate." The instructor hitched the Thor gun a little higher on his hip.

Billy Kasker was silent.

"We will go next to the fields, then to the factory section—such of as there is—then to that part of the city which we have allowed the natives to rebuild. Come."

The class moved out of the city. Here they saw their first natives. Clad mostly in rags—many of them bent and stooped, some of them showing the marks of hunger—they were a quiet people who kept strictly out of the way of the class group. But except for the clothing and the marks of hunger, they were identical in appearance with their conquerors.

"Why, they look just like us!" Joe Buckner said indignantly. He sounded outraged at the resemblance.

"There are many differences," the instructor said quickly. "Note their clothing, how poorly made it is. They make it themselves out of the wool of some kind of animal—deer, I believe, or bear."

"Sheep," Billy Kasker corrected.

"Oh, yes, sheep is the name of the animal. Thank you, Billy."

"You're welcome, sir."

"But they oughtn't to look like us!" Joe Buckner continued.

"There are chemical differences," Susan Sidwell said. "Once, in the laboratory, we analyzed their blood. The color was different for one thing. They also have a much different metabolism."

"But suppose one of them escaped from the museum and got into our part of the world. How would we know he wasn't one of us, if he put on our clothes?" Joe Buckner sounded outraged.

"That is one purpose our bracelets serve," the instructor answered. "A very good question, Joe. As you know, each of us receives a bracelet at birth, which is slipped over the hand and onto the wrist. Made of plasticum, which cannot be cut by any method, the bracelet has the unique property of expanding in size as the wearer grows. It cannot be removed except by cutting off the arm of the wearer." He laughed as if he had made a good joke. "But I am sure no one would ever think of doing that. The bracelet carries the serial number assigned to each of us."

He held up his arm, exhibiting the gleaming circle of plasticum on his wrist. To him—to all of them—it was a badge of honor, a mark that proved one belonged to a superior race. "If one of the natives escaped, the absence of a bracelet would disclose his identity at once. We would take measures to have him eliminated."

"I see," Joe Buckner said. He sounded mollified. "How would we eliminate him?"

"I believe it is customary to use a Thor gun in such cases—a large caliber which will disintegrate him instantly. The model I have will only blast a hole a few inches in diameter."

"I'm going to be a Thorgunman," Joe Buckner said with sudden enthusiasm.

"Good!" the instructor said. "That is a very fine calling. If I had my life to live over again—" He sighed for lost opportunities.

At the announcement of his ambition, Joe Buckner rose higher in the opinion of the class.

"Observe how they make their living," the instructor continued.

The class saw the natives at work tilling the soil. The technique used here was very crude but mildly interesting. They used plows and harrows for loosening the soil, devices that were pulled by large animals.

"Horses, I believe they call the animals. Of course, we don't allow them to have power-drawn equipment."

"It's not at all like the way we obtain our food," Billy Kasker said thoughtfully.

"Oh, no," the instructor answered. "We synthesize our foods. As a matter of fact, they are required to grow their food. That way, they have to spend so much time finding something to eat that they can't cause trouble." He grinned as if something in the idea pleased him.

"Serves them right," Joe Buckner said.

The natives working in the fields seemed not to see the class. When the group came near, they stopped talking and worked harder.

"Scared to talk when we're around," Joe Buckner said. "They're yellow!"

"Now for the factory section," the instructor said.

The factories were small and unimpressive. Working here with very crude tools and with no power equipment, the natives were making farm machinery.

"Why don't we give them better tools?" Billy Kasker asked.

"What have they got coming?" Joe Buckner exclaimed. "They lost, didn't they?"

"Yes, but—"

"If you had your way you'd be sucking in and helping the side that lost. Pretty soon you'd discover you had lost!"

"Hardly that," Billy Kasker replied. "But it seems more human—"

"Human? That's a laugh!" Joe Buckner slapped his thighs and roared with laughter.

"Come along," the instructor said.

"Look—there are children playing games!" Susan Sidwell observed. "Horrible-looking little brats, aren't they?" She pointed to a group of brown-skinned youngsters playing some kind of a game that involved a ball and a club. One threw the ball, the second struck at it with the club.

"What a stupid way to play," Joe Buckner said.

As soon as the young natives saw the graduating group coming, they stopped their game and ran away. They seemed very frightened.

"The young ones fear us," the instructor explained. "The older ones fear us too, but they don't show it so much." He watched the fleeing youngsters with every evidence of great inward satisfaction.

Billy Kasker's lips closed in a thin straight line.

"Now we will go to the rebuilt section."

They walked on.

"One of the natives is following us," Susan Sidwell suddenly said.

Turning, the group saw that a member of the conquered race was coming along the street behind them. He was dressed all in brown—his hat, his shirt, his pants.

The instructor put his hand on the butt of the Thor gun.

The native walked past the group without seeming to see it. He was whistling between his teeth. He walked on ahead of them, turned down an alley, and disappeared. The instructor took his hand off the Thor gun.

"He wasn't really following us; he wouldn't dare. Does anybody have any questions?" He looked brightly around the group.

"Yes, I have," Joe Buckner said. "Why don't we just kill all of these natives? They're not any good to us."

The instructor smiled slyly. "I'll tell you a little secret about that. It's awfully hard to kill all of any race. No matter how thoroughly you do the job, a few always manage to escape. Then they breed and increase in spite of everything you do.

"After we had conquered this planet we had trouble catching all of the natives. They were the most cantankerous, persistent race you can imagine. So these museums were set up, to lure them in here. We announced that these places would be set aside and that they would not be bothered as long as they remained in the museums. All in all, we made the museums rather attractive places, hoping that—"

"I see the plan!" Joe Buckner said glowingly. "After you got them all into the museums—blooie!—knock all of them off at once!"

The instructor smiled. He looked as pleased as if he had thought of the idea himself. A little stir of applause ran through the group as they expressed their gratitude to their rulers for making this world safe for them.

"Why haven't they been killed before now?" Billy Kasker asked. "These museums were opened over forty years ago. Surely—"

"I don't know about that," the instructor answered. "I think probably our rulers are waiting for a propitious time, or perhaps for an incident that will give them an excuse to carry out their plan."

"I hope they don't wait too long," Joe Buckner said. "Golly, I want to be a Thorgunner and get in on the mop-up when it comes!"

The group stirred, seemed to look forward to the day of the final slaughter.

"Any other questions?" the instructor asked.

"I have one," Billy Kasker said hesitantly. "It doesn't exactly have anything to do with our trip through the museum—it's something I ran across in a book—but I don't quite understand it, and I wondered—"

"Go right ahead, Billy. What do you have on your mind?"

"Well, ah, did—did you ever hear of a changeling? I know it's a kind of a silly question but—"

"A changeling?" The instructor frowned.

"I think it comes out of a fairy story or something like that," Billy Kasker said.

"Oh, yes. Now I recall the word." The instructor's face lighted. "It's a story about the fairies taking one child from its crib and substituting another for it. The substituted child was called a changeling. Or perhaps some poor mother, wishing to give her child a better chance, stole the child of a rich mother and put her child in its place. I really don't remember too much about it."

"Thank you, sir. You have explained it very lucidly."

The instructor beamed.

Joe Buckner sniffed. "Asking a question, then telling the instructor he has explained it very clearly when you didn't even ask a sensible question in the first place—that's what I call sucking in! Who ever heard of a changeling?"

The group moved on. They came to the section of the city that had been repaired. The streets had been cleared of the rubble, houses had been rebuilt, and here and there little touches of green grass showed where an attempt to add a touch of beauty had been made.

They saw very few of the natives. Far ahead of them they occasionally glimpsed a native slipping furtively out of the way. Behind them, always at a distance, heads occasionally poked around corners at them.

"They're very cowardly," the instructor said.

"Where's Billy Kasker?" Susan Sidwell suddenly asked.

The group halted. Billy Kasker was no longer following them. A little stir of consternation ran through them as they realized the class president was missing.

"Billy! Billy!" the instructor called.

There was no answer.

"I just don't understand this. He knows he should remain with us."

"Maybe some of these horrible natives grabbed him!" Susan Sidwell said. The group was startled—and suddenly afraid.

The instructor took a deep breath. "I have a Thor gun. I'll go find him. Joe, you are in charge of the group until I return. All of you remain in the middle of the street and don't move."

The instructor went back along the street. He was exasperated and a little alarmed. If anything happened to Billy, how could he explain the matter to the gate captain or to Billy's parents?

"Billy!" he called again and again.

Suddenly he had an answer from an alley.

"Here, sir—here I am. Are you looking for me? I'm sorry, sir." Billy himself appeared in the alley.

Reassured at the sight of the youth, but angry, the instructor moved into the alley. "What is the meaning of this? You have alarmed all of us."

"I'm awfully sorry, sir. But I saw something back here that interested me, and I stopped to take a look. I hope you will forgive me." His manner was so contrite and his chagrin so complete that the instructor had no choice but to forgive him.

"Of course, Billy. But you mustn't do anything like this again. It might be dangerous."

"I won't, sir. I promise. But I wonder, since you are here, if you would be good enough to explain to me the thing I saw back here. It will only take a minute."

"What is it?"

"It's something in one of the houses. I came back looking at something else, then caught a glimpse of this. If you will come into the back yard you can see it. I would really like to have you explain it to me, sir. You are always so clear in your explanations." Billy Kasker's manner was very winning.

"Well, if it will only take a minute—" The instructor followed Billy into the back yard. At the rear was a shed with an open window. A plot of grass separated the shed from the house. On the second floor of the house, a window had been shattered.

"There's something up there in that broken window. If you will come here, sir, you can see it better."

"Um. Ah! Oh, yes." The instructor's back was to the open window of the shed. He stared upward at the house.

Two brown-coated arms came out of the window of the shed and clamped a fierce grip around his throat, jerking him backward against the wall. He grabbed frantically for the Thor gun.

The face of the brown native appeared in the window of the shed. "Get that gun, Billy!"

Billy Kasker was already in action. He snatched the gun from the instructor's flailing hands.

The brown native leaned from the window. Muscles bulging in his powerful arms, he lifted the instructor upward and through the window. A thump came from inside the shed. Billy Kasker, Thor gun ready for use, went through the door.

The instructor was writhing on the floor. The native had a knee on his chest, a knife in his hand.

"This is for the race you think you've conquered!" the native said. He plunged the knife into the instructor's throat. Green liquid spurted from the wound.

"Green blood!" the native said. "One of the chemical differences." He came to his feet. The dying instructor was forgotten. The native's hand went out. "Billy, am I glad to see you. I was afraid you wouldn't recognize me in spite of the tune I was whistling as I walked past you on the street."

"I wouldn't forget," Billy Kasker said.

"But, Billy, it's been twelve years since I traded you, as a kid of five, for one of their brats—changing the bracelet as I changed you. Many times since then I've thought you had forgotten, or that I wouldn't live to see the day when you came back here with a graduating class."

"I don't forget," Billy Kasker said. "I'm even class president!" The words burst out of him as if he was still having trouble understanding what they meant.

"That's wonderful, Billy. You're accepted as one of them, but you're one of us all the time. You're in with them, you're set. You have done a wonderful job and I'm proud of you."

The glow in the native's eyes was a wonderful sight to behold. In it there showed the hope of the future for all the conquered natives of this lost planet that had once been called Earth—the faith, the sure knowledge that they would rise again ... indeed, that they were already rising.

"Thank you! But—" Billy nodded toward the body of the instructor, then spun hastily as a sound came from the rear of the shed, the Thor gun coming to focus. A trap door was rising there. Three natives were looking up from under it.

"They're all right," the brown native said quickly. "They're with us."

Three ragged men scrambled up from below. They looked at the brown native, then at the body of the instructor on the floor. A look of fierce exultation appeared on their faces. Then they looked at Billy Kasker and at the Thor gun he was holding.

"Give the Thor gun to Jim," the brown native said.

Without hesitation Billy Kasker handed the gun to the native who reached for it. Jim did everything but kiss the weapon. "God, the years I've spent dreaming of the moment when I would get one of these babies into my hands! One was all I needed."

"Don't stand there gloating, Jim—get moving," the brown native said. "Within a month I want you not only to know how a Thor gun works but to be manufacturing them by the dozens, including the large sizes. This is the gun that has been stopping us all these years—it is the gun that is going to take us out of these pig pens they call museums. Get moving!"

"Yes, sir." Jim was already gone through the trap door.

The brown native jerked off the instructor's clothes, then worked quickly but deftly with his knife. As he finished, the instructor's hand separated from the arm at the wrist.

"He said no one would ever think of doing anything like that," Billy Kasker said.

"Nobody but one of us stinking natives." The brown man removed the plasticum bracelet, began to work with the fingers of his left hand. "I've spent years learning how to throw my thumb out of joint, just getting ready for the time—"

The plasticum bracelet slipped over the collapsed thumb. It fitted very snugly on his wrist. He held it up.

"Neat, eh. This makes me one of the conquerors."

"A nice fit. But we have very little time. The group will become alarmed."

The second native began to take the instructor's body down the trap door. The brown native swiftly slipped off his clothes and donned the garments the instructor had worn.

"Ed, where's that Thor gun model? I've got to have something that looks and feels like a genuine Thor gun to turn in at the gate."

"Here it is, sir." The third native handed a gleaming replica of the Thor gun to the brown man. He slipped it into the holster. It fitted snugly.

"How do I look, Billy?"

Billy Kasker surveyed the brown native. He was remarkably changed. No longer did he look like one of the natives, he looked like a conqueror. "Just a little higher on the nose with the glasses. And maybe a little less stuffing inside the brim of the hat. But—can you carry off the part of the instructor?"

"I can carry it off or die trying," the brown native said.

"Good!" The two shook hands, then turned and went out the door. As they left, Billy Kasker saw that Ed was mopping the last remnants of the green blood from the floor.

"Perfect, down to the last detail," Billy Kasker said. "You're a genius at planning."

"You have to be a genius to stay alive. Okay, Billy. Here is where we go into our act."

They had moved into the street and the group had seen them. The voice that came from the brown native's mouth was the voice of the instructor, hot and angry.

"Billy, this sort of conduct is intolerable. You know better than to wander off like this. What possible explanation can you offer for your conduct?"

Billy Kasker was very penitent. He was embarrassed, he was humiliated, and he showed both very clearly. He had lost all of his air of easy aplomb. "I'm very sorry, sir. I didn't think—"

"That's just it, you didn't think. You saw nothing in that alley, yet you asked me to come back and look. Is that the way you waste your and my time?"

"It won't happen again, sir," Billy Kasker said contritely.

"See that it doesn't."

"Yah!" Joe Buckner gloated. "This is one time the class president got it in the neck!"

"A very good point you have brought out," the instructor said. "Billy has just demonstrated his unfitness to be class president. I am therefore removing him from this position and appointing you in his stead."

"What?" Joe Buckner gasped, giddy with pleasure.

Billy Kasker took his position in line. No longer did he bring up the rear. Joe Buckner now had that position of honor. The group showed some sympathy for Billy, but not very much or very long. When he lost his position as president they seemed to change their minds about him.

The group moved slowly through the city. As if nothing had happened, the instructor explained what they were seeing. When they asked questions, he answered them. Billy Kasker asked no more questions.

They finally came to the gate and the same resplendent captain greeted them. He accepted the Thor gun and the holster, handed them to the guard.

"How are things in the museum?"

"Everything is in good order, sir."

"Good. I've had the impression they were getting a little restless lately."

"I saw no signs of it."

"Fine. Did you have any trouble with the group?"

"Very little. Billy Kasker wandered off for a few moments and I had to demote him. But it was nothing. See you next year when I bring another graduating class through to show them around."

The group began to separate to go to their own homes. Billy Kasker lingered a little, to speak to the instructor. "I've already asked my folks, sir, so I know it will be all right with them, so if you would like to come home with me tonight—"

"Hmmmm."

"Trying to suck in again," Joe Buckner said. "It won't do you any good now. You're cooked for good this time!"

Billy Kasker seemed not to hear him. His eyes were on the instructor. "We would be very glad to have you, sir. We could talk about a great many things."

"Why, Billy, in that case I will be glad to come home with you."

They moved away together. "There's one thing I want made completely clear," Billy Kasker said.

"What is that?"

"When the time comes, there is one conqueror I've got on my list!"

"That jerk I made class president? Of course, Billy. We will be glad to save him for you alone." The instructor's smile was a happy one.

"Good. That's agreed then." In the gathering dusk, Billy Kasker's voice was as sharp as the edge of a knife driving home into a throat from which green blood spurted....