“What happens if the stresses are too great?”

“Well, we’ll be watching closely. We won’t let it go so far that the plates buckle or the joints fail. But if we have to reduce the thrust, we’ll have other problems. The acceleration would have to be smaller, and then all our other schedules for the new particle defense system would have to change.”

“I see.” Maddy did see — several things. She liked John’s hand on her arm, guiding her along. And he was comfortable again, away from the world of naked ladies and back to his stresses and strains and Poisson’s ratios and buckling coefficients. “Oh, I forgot. What about the new rolfes? Are they on their way from Earth?”

“Not yet. We’re expecting the first ones any day now.”

He did not mention that the arrival of the rolfes would remove Maddy’s reason for remaining on Sky City. She had called Gordy Rolfe two days ago, prepared to offer logic of her own as to why she ought to remain. Gordy had beaten her to it with his first remark: “Hyslop isn’t on the Aten asteroid project anymore.”

“I know.”

“But you stay there. I want you glued to him tighter than ever. Report to me on his every move.”

Gordy had glared at her out of the screen. The scene around him looked like a junkyard, bits and pieces of equipment everywhere. He looked like a junkyard, too, food on his unshaven face and the front of the black jumpsuit, feverish bloodshot eyes and trembling hands.

“But what do I tell Bruno Colombo? I need a reason for staying on Sky City.” She knew that Gordy was in the underground habitat, because she could see the circular wall and the dark green plants beyond it.

“Hell, d’you want me to do your job for you? Tell him anything you like. Sweet-talk Hyslop. Smile at him, show him your tits, open your legs, whatever.”

“I’m not sure that sort of thing works with Hyslop.” It hasn’t so far, and I have been sort of trying. But Gordy can’t be trusted with that sort of detail.

“Fine. It wouldn’t work with me, either. Maybe he’s the one who should be working for Argos instead of you.” Gordy lifted the spindly metal shaft that he was holding in one greasy hand. “All right, here’s what you do. You tell them you have to stay up there until all the new rolfes have arrived, just in case they don’t work right and you have to fix them. That will give you at least ten days.”

“If the rolfes don’t work when they arrive, there’s not much chance I’ll be able to fix them. I’m no great expert when it comes to electronics.”

“Tell me news. It won’t matter. They’ll work exactly as they’re supposed to, and you won’t have to fix a damn thing.”

“How do you know they’ll work?”

He snarled at her. Somehow he had managed to get graphite on his front teeth. They were streaked with black. “The rolfes will work perfectly, because I’m making the fucking things. Personally. Now are you happy? Get back to work. Follow Hyslop, watch what he does. Especially if he starts digging into inventory records and delivery schedules, anything that relates to Argos Group activities. If that happens, you call me at once. Anytime.”

“Anytime?”

“You heard me. You work twenty-four hours a day, the way I do.”

And look the way you do? But he was gone before Maddy could be tempted.

In any case, there was no way to track John Hyslop day and night. Nights could have been easy, but sexually he was the most timid man she had ever met. He found her attractive, she felt sure he did, based on the few occasions when they had both let down their guards. But he never made a move. She had gone as far as she could without grabbing him and dragging him into the bedroom. Was that what he needed? It was about all that was left.

He still had his hand on her arm, leading her. They were going “up” toward the central axis of Sky City, and the centrifugal force against which they climbed was steadily dropping.

“Where are you taking me? To the engineering information center?”

“No, There’s an observation chamber outside the main body of the city, near the power-generating plant. You’ll have the best view from there.”

Maddy had learned the basic geometry and jargon of Sky City. The structure was in orbit around the Earth and at the same time spun around its central axis. That axis always pointed to a fixed direction in space, out toward the cone end of the space shield and Alpha Centauri. The simulation chamber where she and John Hyslop had discovered Lucille DeNorville’s mutilated body lay on the “front” side of the city, the side facing toward the shield. The power-generation plant sat on the “back” side, with the bulk of the city between them and the shield to provide better protection from the particle storm. “We won’t be able to see the shield, will we?”

“Part of it will be in your field of view, beyond the edges of the Sky City disk. But I doubt you’ll actually be able to see it. It’s too tenuous.” They had reached the axis, and John was floating her along the broad air-filled tunnel extending beyond the bulk of Sky City in the direction of the power-generation plant. “Don’t worry; the shield isn’t where the action is. You’ll see everything worth seeing from right here.”

They had come to a fork in the passageway, a place where on one branch a flat hatch was set into the side of the tunnel. John released Maddy’s arm as the hatch began to slide open.

“Won’t we need suits?” Maddy had been warned, over and over. Be careful. Just because you can open a door anywhere on Earth and find air on the other side doesn’t mean you can do the same thing on Sky City.

“They’re available for emergencies. But today this whole segment is at pressure.”

The hatch slid open. Beyond was the observation chamber, and Maddy could see that a few unsuited people were already there.

“Make yourself comfortable.” John glanced at his watch. “Still a few minutes to go. Enjoy the show. The others can answer any questions.”

“What about you? Aren’t you staying?”

“I’d love to. But I’m on duty back inside.” He hesitated, then gave Maddy’s arm a gentle pat and stepped back through the hatch. “As a matter of fact, I’m the one who has to make the final decision on whether to move. Without me in the control chamber there’ll be no show.”

The hatch closed. He was gone. Follow Hyslop all the time? Right, Gordy. Why don’t you tell me how I’m supposed to do that?

Maddy turned. The observation chamber formed a sphere about twelve feet across. It was equipped with gimballed seats that could swing in any direction, and most of the wall consisted of large transparent ports. The chamber was so close to free fall that assignment of direction was a matter of convention. “Above” Maddy lay the ugly tangle of the power-generation facility. “Below” her the main body of Sky City obscured the stars and shield.

The people in the chamber had all glanced at Maddy when she appeared, but now they were again looking outward. She was surprised to find that she recognized every one of them. Closest to her were two of Sky City’s engineering team. They must be “the others” that John had referred to: Lauren Stansfield, as ladylike and elegantly dressed as ever; beside her, Torrance Harbish, lank-haired and saturnine. They were clearly present for some official purpose, because they sat by an array of screens and monitoring devices. In front of the two engineers sat Wilmer Oldfield and Astarte Vjansander, their heads close. Finally, in front of them, hunched so that his chin rested on his chest, was Seth Parsigian. When Maddy moved forward to sit next to him he turned and glared.

She had done what he asked her to, wandering endlessly around the dark corridors and hidden byways of Sky City. With no apparent results, but that was not her fault.

“I thought you were going back to Earth,” she said softly.

“Likewise.” He gave her a quick glance. “An’ we’re both still here. I think they stuck all the Earthsiders out here so we can’t get in the way when they goose the whole place. Look, sometime you and me gotta talk some more.”