"Was it fighting them?" he asked.

"Probably," she answered. "Which means that the Voice is still alive, still controls some functions. Maybe that's why we haven't heard anything further from Bretan Braith. It could be that they're having trouble down there. The Voice would naturally mass its warders to protect the city's life functions." She shrugged. "But it doesn't matter. The Emereli don't hold with violence. The warders are instruments of restraint. They fire sleep-darts, and I think they can emit tear gas from those grills in their base. The Braiths will win. Always."

Behind them the robot was already gone, and the concourse was empty once more. The noises ahead grew very loud.

This time Dirk said nothing when Gwen bore down upon them and turned on her lights, and the screams and the impacts piled one upon the other. She got both of the Braith hunters, although afterwards she said she was not so sure the second one was dead. He'd been hit a glancing blow that spun him to one side, into one of his own hounds.

And Dirk could find no voice at all, because as the man went stumbling and spinning off their right wing he lost his grip on the thing he had been carrying, and it flew through the air and smashed against the window of a shop, leaving a bloody path on the glass when it slid down to the floor. He had been holding it, Dirk noted, by the hair.

The corkscrew road went around and around the tower that was Challenge, sinking slowly and steadily. It took more time than Dirk could have imagined to sink from level 388-where they surprised the second party of Braiths-to level one. A long flight in gray silence.

They encountered no one else, neither Kavalar nor Emereli.

On level 120 a solitary warder blocked their way, turning all its dim eyes on them and commanding them to halt in the voice-still even and cordial-of the Voice of Challenge. But Gwen did not slow, and when she neared, the warder rolled off out of her way, firing no darts and emitting no gas. Its echoing commands chased them down the concourse.

On level fifty-seven the dim lights above them flickered and went out, and for an instant they flew in total darkness. Then Gwen turned on the headlamps and slackened her speed just a bit. Neither of them spoke, but Dirk thought of Bretan Braith and wondered briefly whether the lights had failed or had been turned off. The latter, he guessed; a survivor above had finally called his holdfast-brothers below.

On level one the concourse ended in a great mall and traffic circle. They could see very little of it; only where the beams of the headlamps touched did shapes leap startlingly out of the ocean of pitch that surrounded them. The center of the mall seemed to be a tree of sorts. Dirk caught glimpses of a massive gnarled trunk, a virtual wall of wood, and they could hear leaves rustling above them. The road curved around the great tree and met itself. Gwen followed it, all around the wide circle.

On the far side of the tree a wide gateway stood open to the night and Dirk felt the touch of wind on his face and realized why the leaves had been rustling. As they swept past the gateway, staying on the circle, he looked out. Beyond the gate a white ribbon of road led away from Challenge.

And an aircar was moving low over the road, quickly, toward the city. Toward them. Dirk glimpsed it only for an instant. It was dark-but everything was dark in the meager outworld starlight-and metallic, some misshapen Kavalar beast he could not even begin to identify.

It was not the Ironjades, of that he was sure.

"We have succeeded," Gwen said dryly after they had moved beyond the gate. "They're after us."

"They saw us?"

"They had to. Our light, as we went past the open gateway. They couldn't miss that."

Thick darkness rushed by them on either side, and the leaves still rustled above their heads. "We run?" Dirk said.

"Their car will have working lasers, and ours doesn't. The outer concourse is the only road open to us. The Braith aircar will chase us up, and somewhere above us the hunters will be waiting. We only killed two, maybe three. There will be more. We're trapped."

Dirk was thoughtful. "We can loop around the circle again, go out the gate after they've entered."

"Yes, that's an obvious try. Too obvious, though. There will be another aircar outside waiting for us, I'd guess. I have a better idea." As she spoke, she slowed the manta and brought it to a halt. Immediately before them the road forked, amid the bright wash of the headlamps. To the left the traffic circle curved back on itself; to the right was the outer concourse, beginning its two-kilometer ascent.

Gwen turned off the lights and darkness engulfed them. When Dirk started to speak, she quieted him with a sharp "Sssh!"

The world was very black. He had gone blind. Gwen, the aircar, Challenge-everything had vanished. He heard leaves brushing against each other, and he thought he heard the other aircar, the Braiths, coming down on them, but that had to be his mind, for surely he would first have seen their lights.

There was a gentle rocking motion, as if he were sitting in a small boat. Something hard touched his arm, and Dirk started, and then other somethings scraped against his face.

Leaves.

They were rising, right up into the low-hanging dense foliage of the great spreading Emereli tree.

A branch, pushed down and then released, whipped him painfully across the cheek, drawing blood. Leaves pressed all around him. Finally there was a soft thud as the wings of the manta came hard against the bulk of a massive limb. They could rise no more. They hovered, blind, enveloped by darkness and unseen foliage.

A very short time later a blur of light flashed by beneath them, curving off to the right, up the concourse. No sooner was it gone than another came into sight-from the left-turned sharply up the fork, and followed the first. Dirk was very grateful that Gwen had ignored his suggestion.

They hovered amid the leaves for an endless time, but no other cars appeared. Finally Gwen lowered them back to the road. "That won't lose them permanently," she said. "When their trap closes and we're not in it, they'll begin to wonder."

Dirk was dabbing at the wetness on his cheek with his shirttail. When his fingers finally told him that the thin trickle of blood had dried, he turned in the direction of Gwen's voice. He was still blind. "So they'll hunt for us," he said. "That's good. While they're being bothered by trying to figure out where we went, they won't be killing any Emereli. And Jaan and Garse should get here soon. Now is the time for us to hide, I think."

"Hide or run," came Gwen's answer from the darkness. She still had not touched the aircar lights.

"I have an idea," Dirk said. He touched his cheek again. Then, satisfied, he began to tuck away his shirttails. "When you were swinging around the circle I noticed something. A ramp, with a sign. Just saw it briefly in the headlamps, but it reminded me. Worlorn has a subway network, right? Intercity?"

"True," Gwen said. "It's dismantled, though."

"Is it? I know the trains don't run, but what about the tunnels? Did they fill them in?"

"I don't know. I hardly think so." Suddenly the air-car's headlamps woke again, and Dirk blinked at the sudden light. "Show me this sign," Gwen said, and once more they began the wide circuit around the central tree.

It was a subway entrance, as Dirk had guessed. A shallow ramp led down into darkness. Gwen stopped their forward motion and left them hovering a few meters away while she played the headlamps over the sign. "It will mean abandoning the aircar," she said at last. "Our only weapon."

"Yes," Dirk said. The entrance was much too narrow for the gray metal manta to pass; clearly the subway builders had not counted on anyone wanting to fly through their tunnels. "But that might be best. We can't leave Challenge, and inside the city the car limits our mobility pretty severely. Right?" When Gwen did not answer immediately, he rubbed his head wearily. "It sounds right to me, but maybe I'm not thinking so clearly. I'm tired and I'd probably be scared if I stopped to think about this. I've got bruises and cuts and I want to get some sleep."