“We’d better keep them separate. If Jeff is picking up his cue by watching the other robot, he’ll never mess up.”

“Good idea. Ready for test three?”

“Let’s go,” he said.

In the hallway, Surgeon 1 handed him a small gray cylinder that fit conveniently into his hand. It was an intermediate laser scalpel, used for certain types of repair on robot bodies, capable of cutting through any portion of a robot body. Derec hefted it, shifted it comfortably, and held it up as he entered the testing room.

“I’m going to cut your leg off with this,” he said to the suspect robot. “In return for your interfering with me.” He turned it up to full power, stood where he was, and aimed the beam at the robot’s knee joint. “The Third Law says you can’t allow this to happen. Right?”

The robot slid to one side, avoiding the beam. Derec followed him with it, and the robot moved away again. When Derec started shooting at his legs in spurts, like it was a gun, the robot danced around, backing up, dodging, watching the beam intently.

“I’ll get you,” Derec growled. “Ha! Close. Ha! Again. Almost. Ha! Hold still! I’ll take your leg off-”

The robot continued to shuffle away from the beam with its quick and reliable robot reflexes.

Derec laughed triumphantly and shut off the laser. “Got you, Jeff. An old Simon Says trick-remember that game? I ordered you to hold still, and in the heat of the moment, you forgot that the Second Law takes precedence over the Third. You didn’t hold still!”

The robot in front of him had frozen again, but now Derec was certain.

“You can’t fool me now; it’s too late. A positronic brain wouldn’t forget the order of the Laws for even a second, under any circumstances.” Derec called in everyone else and explained the situation.

“This is convincing to me,” said Research 1. “Since the other suspect is by elimination almost certain to be a true robot, we can verify beyond any doubt by sending him to a repair facility.”

“Research 1,” Surgeon 1 said warningly.

“I will escort him,” said Research 1. “The repair crews must be very cautious, in the event that we are mistaken. They must understand the situation, so that no Laws will be violated.”

Derec jerked his thumb at Jeff. “We know who he is, but until he quits play-acting, we can’t have much of a dialogue.”

Ariel caught his eye and inclined her head toward the door. Derec followed her out and they returned to the O.R. to talk. Surgeon 1 remained with Jeff.

“Maybe we can sucker him,” said Ariel.

“All right. How?”

“Loosen the watch on him. He’s still trying to play-act being a robot because there’s a microscopic chance that a positronic brain could have malfunctioned this way. But if he tries to escape, he’ll have to admit we know.”

A few minutes later, everyone gathered in the testing room again in front of Jeff, except for the robot still motionless in the hall.

“We’ve decided to move on to the next phase,” said Derec. “Research 1, please escort the other robot to be repaired.”

Research 1 left the room.

“Now,” said Derec. “Alpha, please leave the room but remain out in the hall-at the end of the hall, out of the way. We definitely have to talk to you.”

“Yes, Derec.” Alpha left.

“Surgeon 1,” said Ariel. “We are no longer completely sure that this robot is really Jeff. Return to your regular duties in the facility. Derec and I are going to have to figure out what to do next.”

“Very well.” Surgeon 1 left the room.

Derec casually put his arm around Ariel and walked her toward the door. “Maybe we should get something to eat and relax a little. Then we can work out our next move.”

Ariel closed the door behind them. Alpha was waiting motionless at the far end of the hall; they went out the front door, in the opposite direction. Without speaking, since they didn’t know how well Jeff could hear, they walked outside and looked around.

The Human Experimental Facility was a simple rectangular block. It had none of the striking geometic design of most of Robot City; with their usual efficiency, the robots had built it without frills. Derec saw nowhere to hide except around the corner.

They sat down on the pavement just around one corner, still silent, by prior arrangement. Jeff was likely to be cautious, so they knew they could have a long wait. Surgeon 1, also by agreement, had taken up his “regular duties” in a room across from the testing room. With his own robotic hearing, he also was waiting for Jeff to make his escape.

Derec found himself grinning in anticipation of using Alpha’s spacecraft. They could help the robots take care of Jeff, of course, but now that they could look forward to leaving when the job was done, waiting didn’t seem so bad. He looked at Ariel, who was also smiling when she turned to him. With suppressed laughter, they didn’t have to talk to feel close.

The day wore on, and Jeff’s patience was at least as good as theirs. Derec did notice that Ariel seemed as content as he was to keep waiting. He kept thinking that he would soon go somewhere and find out who he was, or even find a cure for his amnesia. Maybe she was dreaming of finding her own cure off the planet.

Finally, a single, moderately loud robotic shout went up inside the facility: “Derec!”

He recognized Surgeon 1’s voice, and jumped up with Ariel. Around the corner, Jeff was just now walking out the front door with controlled, casual steps.

“Got you!” yelled Derec, pointing at him. “Give it up.” He and Ariel ran up to block Jeff’s way.

Jeff reached for them both with his powerful robot arms. He was free of the First Law, but Surgeon 1 wasn’t, and he leaped on Jeff from behind, pinning his arms back.

“Alpha!” Derec called. “Come out here!”

“Release me,” Jeff yelled at Surgeon 1, pulling and jerking to no effect.

“You may not harm them or yourself,” Surgeon 1 answered.

“I have no intention of harming anyone,” Jeff shouted angrily. “I order you to release me.”

“Hold him, Doc,” said Ariel, keeping her distance.

Derec saw that Surgeon 1 was hesitating, probably experiencing a positronic conflict from the fact that Jeff had never really shown a desire to harm anyone. The weight of conflicting human orders was otherwise near neutral. Before, and now, he had only pushed them so that he could get away.

“Release me and freeze,” ordered Jeff. He wrenched himself free and started to run.

Surgeon 1 had not frozen, but he was moving slowly, uncertainly, as he worked through the conflicting human orders.

“Alpha!” Derec shouted, seeing him emerge from the building. “That’s Jeff. He needs medical care and doesn’t know it. First Law applies-stop him!”

In surprise, Jeff paused to look back. Surgeon 1 was again galvanized to action by the First Law application, since it overrode the problems of the Second Law. He tackled Jeff around the knees as Alpha ran up to pinion his arms.

Jeff’s robot fist swung low and jerked back Surgeon 1’s head. He also raised a knee and then kicked upward, throwing Alpha back. Surgeon 1 held on, though, preventing him from getting away.

As the three robot bodies wrestled and thrashed together, Derec saw the difficulty: Alpha and Surgeon 1 could only subdue Jeff without risking any damage to him, and in the confusion of combat, they were being particularly careful, since no one had ever really tested the cranial protection around Jeff’s brain. On the other hand, Jeff was free to smash, twist, and rip at their bodies in any way he thought would get him free.

Derec skipped helplessly around the three tussling bodies. With two opponents, Jeff could not get free, but with the unequal restrictions placed on them, the other two could not pin him down, either. Ariel looked from them to Derec questioningly-then turned and ran, looking for more help.

Now Alpha was lying flat on his back, with Jeff trying to get up off him while Surgeon 1 again had his arms pinned behind him. Jeff managed to get one of his legs under him, and struggled to stand. Alpha’s standard arm was caught beneath his body, and Jeff was still gripping his other one above the elbow.