“Well, I’m not sick anymore!” She folded her arms. “I’m well now, at least physically.” She watched him for a moment. Then, as if to prove the point, she knelt down and started feeling around the surface of the platform herself.

“You don’t even remember being here before, do you?” Derec asked accusingly. The tension was making him irritable.

“Do you?”

“Yes!”

“Well…you haven’t known who you are for the entire time I’ve known you. You’ve had amnesia since…” She shook her head, shaking off the thought. “I may not have adjusted to everything, but at least I have something.” Then she hesitated, searching his face. “I didn’t mean to say that. Not out loud, anyway. Did I get that right? Or did I remember wrong?”

Derec shook his head shortly and turned away. “That’s right.” She had even phrased it much the same way on earlier occasions. He shifted around on his knees, feeling for an irregularity in the smooth surface. “Mandelbrot, can you see anything?”

“Here,” said Mandelbrot, walking to a far corner of the platform. “My vision has identified a small square outline that likely represents the opening.”

“Good.” Derec walked over to Mandelbrot and knelt at the robot’s feet. He slid his hands along the sides of a rectangular hairline break in the platform floor until he felt a small depression in the surface, no larger than a thumbhold. He braced himself and started to slide it to one side.

“Allow me,” said Mandelbrot.

“No, I got it-” Derec stopped, as the robot gently grasped his forearm and pulled it away. He turned to look up. “Mandelbrot, what are you doing?”

“How much have the chemfets in your body weakened you?” Mandelbrot asked.

“Not that much! Now let’s quit talking and get down there. Avery put ‘em in me and he’s the only one who can get ‘em out. Come on!” Derec pulled away from the robot again.

“Derec?” Ariel said tentatively.

“Mandelbrot,” said Derec, “carry Wolruf and come down last. Help Ariel over the-”

“I cannot. I must open it and go first.”

“What?”

“The First Law of Robotics,” said Mandelbrot mildly. “I can’t harm a human or let one come to harm-”

“I know!” Derec shouted angrily. “Don’t you lecture me on the Laws. I put you together, remember? I know those Laws inside out, outside in, upside down-”

“I said it for Ariel’s benefit,” said Mandelbrot. “Perhaps her memory of the Laws is not clear.”

“I remember that one.” Ariel looked embarrassed by the confrontation. “Uh-is the Second Law the one that says a robot must obey orders from a human?”

“Yes, unless the orders conflict with the First Law.” Mandelbrot nodded.

“Then the Third Law must be the one that says a robot can’t let itself come to harm or harm itself. “

“As long as this doesn’t conflict with the First or Second Laws,” Mandelbrot finished. “Correct.”

Ariel smiled faintly.

“Let’s get going,” said Derec impatiently. He reached for the thumbhold again, though he did not expect Mandelbrot to let him open the door now, either.

“I will determine this situation,” said Mandelbrot firmly. “With all due respect, the Laws require it.”

“How do you figure that?” Derec demanded.

“Your motor control of your own body is gradually failing because of the chemfets in your body. Ariel is disoriented because of her memory transfer, and Wolruf’s body is unsuited to climbing down at this steep angle. We are about to enter the office and possible temporary residence of your nemesis. The likelihood of harm to you is high; therefore, I shall go first.”

Derec glared at him, unable to argue with his robotic logic.

Wolruf looked up at him, cocking her doglike face to one side. “Arr ‘u going to carry me down?”

“I will enter alone, first,” said Mandelbrot. “Derec’s knowledge of Robot City makes him the best able to handle unexpected developments, so he will follow me if the room offers no danger. I will carry you down if we all go.”

Wolruf nodded assent.

Derec watched Mandelbrot in the faint light. The robot hesitated just a moment, probably looking with infrared sensors and listening for signs of habitation or danger within. Then he bent down and slid the trapdoor open slightly. After another pause, he opened the trap fully and climbed down a metal ladder inside the door.

Derec waited, hardly daring to breathe. Avery could easily have a trap waiting for them. Wolruf moved to his side. Ariel stood quietly, but seemed relaxed, as though she did not understand the gravity of the situation.

After what seemed like a long time, a light came on in the room, throwing a cone of light upward. Mandelbrot called up softly. “It is here and unoccupied, apparently safe for everyone.”

Derec let out a breath of relief and took Ariel’s arm. “You go next. Never mind what he said about me handling the unexpected; he can protect you better if anything happens. And he’ll help you if you have trouble with the ladder.”

“All right.” Ariel started climbing down carefully.

Wolruf came to the edge of the opening and peeked down cautiously, being careful not to get in the way.

Derec took the time to move with similar caution to the edge of the Compass Tower. So far, he could see no changes down below that indicated an alert.

Wolruf went next. Then Derec started down, hoping his hands and feet would obey him. He descended slowly into the room, holding the ladder tightly. When he was fully inside, he slid the door shut over his head.

The ladder was firm and not difficult to negotiate. Just before he reached the floor, however, the muscles of his right leg failed to respond. His foot slipped off the bottom rung and he stumbled back into the arms of Mandelbrot.

Derec pulled himself away, glaring at the others, who were all watching him. “I just slipped, all right?”

None of them answered.

“Come on, come on. Let’s find out what we can.” Derec moved past Mandelbrot to pace around the office, looking around.

At first glance, it was just as he remembered. The only other time he had been here, Ariel had remained inside only a moment or two, so she would have few memories of the interior even at her best. The other two had never been here at all.

The walls and the ceiling were entirely viewscreens, displaying a panoramic view of Robot City at night on all sides. It was nearly identical to the view Derec had seen from the platform just above the room. The buildings of Robot City sparkled in all directions as far as he could see. In the ceiling, they could see the blue sky still above them.

The office was furnished with real furniture, all brought from another planet; easy chairs, couch-bed, and an iron-alloy desk, instead of the simple utilitarian furniture made in Robot City. A blotter with paper and two zero-g ink pens were on the desk. As before, a small, airtight shelf full of tapes was intact. They were separated by subject and then by planet, as he recalled, representing all fifty-five Spacer worlds. If anyone had used them, they had all been replaced in order. Nothing seemed changed since his last visit until he turned and saw the plant.

Before, an unfamiliar plant had been flourishing under a growth light. The light was still in place, but the plant beneath it lay limp and dried in its pot. Its stalks were lavender, but he had no idea if that was a sign of recent dessication or its normal color in death. He crumpled a dead leaf thoughtfully in one hand.

“Someone just let it die,” said Ariel, joining him.

“I don’t think anyone’s been here,” said Derec. “Mandelbrot, Wolruf -does anyone see any sign of recent habitation here?”

Ariel looked around the room, and then down into a small waste basket. “This is empty.”

“Someone has been here since I was here last, then,” said Derec. “But that was a long time ago.” He turned back to the desk with a sudden memory. Before, a holo cube with a picture of a mother and baby had been on it. The cube was gone.