All of the car scouts, of course, went armed, and in the early days a number of them had experimented. Coming upon a small herd, they would cut out a number of the better ones, blasting the rest. Disconnecting the think boxes, they would have their partners drive them back. But attempts at rehabilitation had been something less than successful. Even a complete wipe, followed by reprogramming, did not render the susceptible individuals immune to relapse. Murdock even recalled one that had behaved normally for almost a year, until one day in the midst of a traffic jam it had monoed its driver and taken off for the hills. The only alternative was to discard the entire computational unit and replace it with a new one which was hardly worthwhile, since its value was far greater than that of the rest of the vehicle.

No, there had been no answer in that direction. Or any other but the course that he had followed; track and attack, the systematic destruction of the herds. Over the years his respect for the cunning and daring of the herd leaders had grown. As the wild ones had dwindled in number, their ferocity and guile had reached the level of legend. There had been nights, as he lay sleeping, that he dreamed of himself as a wild car, armed, racing across the Plains, leader of a herd. Then there was only one other car, a red one.

The herd began its turn. Murdock saw, with a sudden pang of regret, that it was heading into the far eastern canyon. He tugged at his white-streaked beard and cursed as he reached for his stick and began to rise. True, there would still be plenty of time to get over to the next canyon for the kill, but- No! Some of them were splitting off, heading this way!

Smiling, he drew himself upright and limped rapidly down the hill to where the Angel of Death waited for him. He heard the exploding mines as he climbed into the vehicle. It's motor began to hum.

"There are a few in the next canyon," came the soft, well-modulated, masculine voice of his machine. "I have been monitoring all bands."

"I know," he answered, stowing his stick. "Let's head over that way. Some will make it through."

Safety restraints snapped into place around him as they began to move.

"Wait!"

The white vehicle halted.

"What is it that you wish?"

"You are heading north."

"We must, to exit here and enter the next canyon with the others."

"There are some connecting side canyons to the south. Go that way. I want to beat the others in."

"There will be some risk involved."

Murdock laughed.

"I've lived with risk for a quarter of a century, waiting for this day. I want to be there first for the end. Go south!"

The car swung through a turn and headed southward.

As they cruised along the arroyo bottom's sand, Murdock asked, "Hear anything?"

"Yes," came the reply. "The sounds of those who were blasted by the mines, the cries of those who made it through."

"I knew some would make it! How many? What are they doing now?

"They continue their flight southward. Perhaps several dozen. Perhaps many more. It is difficult to estimate from the transmissions."

Murdock chuckled.

"They've no way out. They'll have to turn sooner or later, and we'll be waiting."

"I am not certain that I could deal with a mass attack by that many-even if most lack special armaments."

"I know what I'm doing," Murdock said. "I've chosen the battleground."

He listened to the muffled thuds of the distant explosions.

"Prime the weapons systems," he announced. "Some of them could have located the sideway we'll be taking."

A twin band of yellow lights winked out on the dashboard and were replaced by a double row of green ones. Almost immediately these faded and were succeeded by two lines of steady, red points.

"Ready on rockets," came the voice of the Angel.

Murdock reached out and threw a switch.

A larger light had also come on-orange and pulsing faintly.

"Cannon ready."

Murdock threw a larger switch beside a pistol grip set in the dash below it.

"I'll keep this one on manual for now."

"Is that wise?"

Murdock did not answer. For a moment he watched the bands of red and yellow strata to his left, a veil of shadow being drawn slowly upward over them.

"Slow now. The sideway will be coming up shortly. It should be up there on the left."

His car began to slow.

"I believe that I detect it ahead."

"Not the next one. It's blind. There's one right after it, though. It goes through."

They continued to slow as they passed the mouth of the first opening to the left. It was dark and angled off sharply.

"I've become aware of the next one."

"Very slowly now. Blast anything that moves."

Murdock reached forward and took hold of the pistol grip.

Angel braked and made the turn, advancing into a narrow pass.

"Dim the ready lights. No transmissions of any sort. Keep it dark and quiet."

They moved through an alley of shadow, the distant explosions having become a pulsing more felt than heard now. Stony walls towered on either hand. Their way wound to the right and then to the left.

Another right-hand twisting, and there was a bit of brightness and a long line of sight.

"Stop about three meters before it opens out," Murdock said, not realizing until moments later that he had whispered.

They crept ahead and came to a halt.

"Keep the engine running."

"Yes."

Murdock leaned forward, peering into the larger canyon running at right angles to their own. Dust hung in the air-dark, murky below, sparkling higher above, where the sun's rays could still reach.

"They've already passed," he reflected "and soon they should realize they're in a box -a big one, but still a box. Then they'll turn and come back and we'll open up on them." Murdock looked to the left. "Good place right over there for some more of our people to lay up and wait for them. I'd better get in touch and let them know. Use a fresh scrambler this time."

"How do you know they'll be coming back? Perhaps they'll lay up in there and make you come in after them."

"No," Murdock said. "I know them too well. They'll run for it."

"Are you sure there aren't any other sideways?"

"None going west. There may be a few heading east, but if they take them, they'll wind up in the other trap. Either way, they lose."

"What if some of those others cut down this way?"

"The more, the merrier. Get me that line. And see what you can pick up on the herd while I'm talking."

Shortly after that, he was in touch with the commander of the southern wing of the pursuers, requesting a squad of armed and armored vehicles to be laid up at the point he designated. He learned that they were already on their way to the western canyon in search of those vehicles observed entering there. The commander relayed Murdock's message to them and told him that they would be along in a matter of minutes. Murdock could still feel the shock waves from the many explosions in the eastern canyon.

"Good," he said, and he ended the transmission.

"They've reached the end," the Angel announced a little later, "and are circling. I hear their broadcasts. They are beginning to suspect that there is no way out."

Murdock smiled. He was looking to his left, where the first of the pursuing vehicles had just come into sight. He raised the microphone and began giving directions.

As he waited, he realized that at no time had he relaxed his hold on the pistol grip. He withdrew his hand, wiped his palm on his trousers, and returned it.

"They are coming now," the Angel said. "They have turned and are headed back this way."

Murdock turned his head to the right and waited. The destruction had been going on for nearly a month, and today's should be the last of it. He suddenly realized just how tired he was. A feeling of depression began to come over him. He stared at the small red lights and the larger, pulsing orange one.