“Nanny, what are you doing?” Jean scrambled nervously to her feet. Bobby leaped up, too. “Nanny! What’s going on?”

“Let’s go.” Jean said, frightened. “Let’s go home.”

“Come on, Nanny,” Bobby ordered. “We’re going home, now.”

The green Nanny moved away from them; it was totally unaware of their existence. Down the lake-side the other Nanny, the great orange Nanny, detached itself from the little girl and began to flow.

“Nanny, you come back!” the little girl’s voice came, shrill and apprehensive.

Jean and Bobby rushed up the sloping lawn, away from the lake. “She’ll come!” Bobby said. “Nanny! Please come!”

But the Nanny did not come.

The orange Nanny neared. It was huge, much more immense than the blue Mecho jaw-model that had come into the back yard that night. That one now lay scattered in pieces on the far side of the fence, hull ripped open, its parts strewn everywhere.

This Nanny was the largest the green Nanny had ever seen. The green Nanny moved awkwardly to meet it, raising its grapples and preparing its internal shields. But the orange Nanny was unbending a. square arm of metal, mounted on a long cable. The metal arm whipped out, rising high in the air. It began to whirl in a circle, gathering ominous velocity, faster and faster.

The green Nanny hesitated. It retreated, moving uncertainly away from the swinging mace of metal. And as it rested warily, unhappily, trying to make up its mind, the other leaped.

“Nanny!” Jean screamed.

“Nanny! Nanny!”

The two metal bodies rolled furiously in the grass, fighting and struggling desperately. Again and again the metal mace came, bashing wildly into the green side. The warm sun shone benignly down on them. The surface of the lake eddied gently in the wind.

“Nanny!” Bobby screamed, helplessly jumping up and down.

But there was no response from the frenzied, twisting mass of crashing orange and green.

“What are you going to do?” Mary Fields asked, tight-lipped and pale.

“You stay here.” Tom grabbed up his coat and threw it on; he yanked his hat down from the closet shelf and strode toward the front door.

“Where are you going?”

“Is the cruiser out front?” Tom pulled open the front door and made his way out onto the porch. The two children, miserable and trembling, watched him fearfully.

“Yes,” Mary murmured, “it’s out front. But where—”

Tom turned abruptly to the children. “You’re sure she’s—dead?”

Bobby nodded. His face was streaked with grimy tears. “Pieces … all over the lawn.”

Tom nodded grimly. “I’ll be right back. And don’t worry at all. You three stay here.”

He strode down the front steps, down the walk, to the parked cruiser. A moment later they heard him drive furiously away.

He had to go to several agencies before he found what he wanted. Service Industries had nothing he could use; he was through with them. It was at Allied Domestic that he saw exactly what he was looking for, displayed in their luxurious, well-lighted window. They were just closing, but the clerk let him inside when he saw the expression on his face.

“I’ll take it,” Tom said, reaching into his coat for his checkbook.

“Which one, sir?” the clerk faltered.

“The big one. The big black one in the window. With the four arms and the ram in front.”

The clerk beamed, his face aglow with pleasure. “Yes sir!” he cried, whipping out his order pad. “The Imperator Delux, with power-beam focus. Did you want the optional high-velocity grapple-lock and the remote-control feedback? At moderate cost, we can equip her with a visual report screen; you can follow the situation from the comfort of your own living room.”

“The situation?” Tom said thickly.

“As she goes into action.” The clerk began writing rapidly. “And I mean action–this model warms up and closes in on its adversary within fifteen seconds of the time its activated. You can’t find faster reaction in any single-unit models, ours or anybody else’s. Six months ago, they said fifteen second closing was a pipe dream.” The clerk laughed excitedly. “But science strides on.”

A strange cold numbness settled over Tom Fields. “Listen,” he said hoarsely. Grabbing the clerk by the lapel he yanked him closer. The order pad fluttered away; the clerk gulped with surprise and fright. “Listen to me,” Tom grated, “you’re building these things bigger all the time– aren’t you? Every year, new models, new weapons. You and all the other companies—building them with improved equipment to destroy each other.”

“Oh,” the clerk squeaked indignantly, “Allied Domestic’s models are never destroyed. Banged up a little now and then, perhaps, but you show me one of our models that’s been put out of commission.” With dignity, he retrieved his order pad and smoothed down his coat. “No, sir,” he said emphatically, “our models survive. Why, I saw a seven-year-old Allied running around, an old Model 3-S. Dented a bit, perhaps, but plenty of fire left. I’d like to see one of those cheap Protecto-Corp. models try to tangle with that.”

Controlling himself with an effort, Tom asked: “But why? What’s it all for? What’s the purpose in this—competition between them?”

The clerk hesitated. Uncertainly, he began again with his order pad. “Yes sir,” he said. “Competition; you put your finger right on it. Successful competition, to be exact. Allied Domestic doesn’t meet competition—it demolishes it.”

It took a second for Tom Fields to react. Then understanding came. “I see,” he said. “In other words, every year these things are obsolete. No good, not large enough. Not powerful enough. And if they’re not replaced, if I don’t get a new one, a more advanced model—”

“Your present Nanny was, ah, the loser?” The clerk smiled knowingly. “Your present model was, perhaps, slightly anachronistic? It failed to meet present-day standards of competition? It, ah, failed to come out at the end of the day?”

“It never came home,” Tom said thickly.

“Yes, it was demolished … I fully understand. Very common. You see, sir, you don’t have a choice. It’s nobody’s fault, sir. Don’t blame us; don’t blame Allied Domestic.”

“But,” Tom said harshly, “when one is destroyed, that means you sell another one. That means a sale for you. Money in the cash register.”

“True. But we all have to meet contemporary standards of excellence. We can’t let ourselves fall behind … as you saw, sir, if you don’t mind my saying so, you saw the unfortunate consequences of falling behind.”

“Yes,” Tom agreed, in an almost inaudible voice. “They told me not to have her repaired. They said I should replace her.”

The clerk’s confident, smugly-beaming face seemed to expand. Like a miniature sun, it glowed happily, exaltedly. “But now you’re all set up, sir. With this model you’re right up there in the front. Your worries are over, Mr… .” He halted expectantly. “Your name, sir? To whom shall I make out this purchase order?”

Bobby and Jean watched with fascination as the delivery men lugged the enormous crate into the living room. Grunting and sweating, they set it down and straightened gratefully up.

“All right,” Tom said crisply. “Thanks.”

“Not at all, mister.” The delivery men stalked out, noisily closing the door after them.

“Daddy, what is it?” Jean whispered. The two children came cautiously around the crate, wide-eyed and awed.

“You’ll see in a minute.”

“Tom, it’s past their bedtime,” Mary protested. “Can’t they look at it tomorrow?”

“I want them to look at it now.” Tom disappeared downstairs into the basement and returned with a screwdriver. Kneeling on the floor beside the crate he began rapidly unscrewing the bolts that held it together. “They can go to bed a little late, for once.”

He removed the boards, one by one, working expertly and calmly. At last the final board was gone, propped up : against the wall with the others. He unclipped the book of instructions and the 90-day warranty and handed them to Mary. “Hold onto these.”