Slowly, sprawled hard against the wall, each limb moving in turn, he inched upward.

He could see nothing but the wall inches from his eyes, feel nothing but the drag at his arms, the awkward twist of his legs. Each time he freed a pad meant a cautious twisting, to fasten them a careful movement Sweat began to run from his forehead into his eyes and he felt the clammy touch of it beneath his clothing.

Grimly he climbed on, inches at a time, muscles aching in thighs and groin, cramps threatening his shoulders and calves.

From below came the encouraging voice of the engineer.

"Keep going, Earl! You're doing fine!"

"How high am I?"

"Maybe thirty feet!"

Less than a third of the distance covered. Thirty feet out of a hundred and already the strain of hauling his body up the sheer wall was beginning to tell. Pausing, Dumarest hung to rest, turning his head to see the sea of vegetation, the ship rearing against the sky. The light from the suns was dazzling, reflected from the wall it hurt his eyes. Closing them he released one leg, flexing it to ease the strain.

"Up!" snapped Sufan Noyoka. "Earl, what are you waiting for?"

Dumarest made no answer, easing each limb in turn, then doggedly continued to climb. At sixty feet progress slowed, the pads seeming to slip, and after another five feet he was sure of it. Watching, he placed his arm into position, heaved, saw the attachments move down the wall as if they glided on oil.

Cautiously he moved to one side, tried to climb again but with no better result. Tilting his head he looked at the top of the wall. He was two-thirds of the way up, a little more and he would be home, but the last few feet were impossible to cover.

Timus caught him as he dropped from the wall.

"Earl? Are you all right?"

"Cramp." Dumarest doubled, kneading his legs. His shoulders ached and his arms burned. He had climbed mountains with less bodily fatigue. "Maybe something in the wall. I don't know."

"So you failed." Sufan was bitter. "A few more feet, couldn't you make it?"

"I tried." For too long and too hard. The red sun was setting, the yellow taking its place. "The wall won't hold the suction cups up there. They slip."

"And?"

Dumarest shrugged. "I don't know. Maybe Marek has an idea."

* * *

He sat as usual in the salon, toying with his cards, his face smooth, apparently unconcerned, but one whose brain was never still. A man who had boasted of his talent, one who had now to prove his claims.

"A problem," he said. "A puzzle, and each tackles it in his own way. Acilus tried brute force, you were more subtle, Earl, but with no greater success. Yet such attempts had to be made and the use of suction cups was clever. A lighter person, perhaps? But no. You alone have to have the physical attributes necessary for such a climb. What else? Well, first let us study the situation."

"We've done that," said Sufan curtly. "A city locked behind a wall."

"Exactly, a wall." Marek turned some cards, his eyes bland. "Now, what is a wall? It is a barrier set to keep others out. But that same barrier will keep others in. Perhaps the city is a prison built to contain some criminal form of life. A possibility, you must admit, and one which must be considered. For while every prison must have a key it is equally true to state that no prison can be entered without it having a door."

"I have no patience to listen to abstruse meanderings, Marek."

"Yet patience in this matter is essential. Earl advised it, Acilus rejected it, and by so doing, lost his life. Jarv also was impatient and Jarv is dead." His voice hardened a little to take on an edge. "I have no wish to join them, Sufan. Not yet. And not because you refuse to wait."

"Then tell us how to enter the city."

"Find the door."

"What?" Sufan frowned, his eyes coming to rest, sharp in their anger. "I warn you, Marek-"

"Again a warning!" Marek threw down the cards. "I grow tired of warnings. You have seen what I have seen, know what I know. The city is an enigma. To understand it I must study it. Why are the mounds set in such a fashion? What is the purpose of the spire? Why is the wall so high and why does its surface alter toward the summit? Why the clearing?"

"That is to keep the vegetation from growing too close to the wall. That's obvious."

"But not necessarily true." Marek leaned back, resting the tips of his fingers together, an attitude Dumarest found at variance to his character.

He said, without irony, "Is the puzzle too simple, Marek?"

"Earl, you have it! What could be more simple than an apparently impenetrable wall? You, at least, do not fall into the common error of believing that complexity makes for difficulty. The reverse is true; the more complex a thing, the more parts there are in relation to each other, the more simple it is to determine an answer. Find me the door and I will lead you into the city. But first I must locate the door."

"But how?" Timus was baffled. "We've looked, there is no door. Earl?"

Dumarest said, "You think about it, Timus. I need a shower."

Embira was waiting as he stepped from the cubicle. She wore a close-fitting gown of silver laced with gold, a perfect accompaniment to her skin and hair. She moved toward him, one hand trailing the wall.

"Earl?"

"Yes." He took her hand. "I thought you were asleep."

"I was, but I've rested long enough. Take me outside, Earl. The metal," she gestured toward the hull, "cramps me."

Outside the air was brooding with a heavy stillness, the sky painted with a profusion of light. The red sun was low on the horizon, the yellow on its upward climb, the blue barely visible. Three suns that bathed the city with light. From the summit of the mound Dumarest looked at it, then at the girl. She was frowning.

"Something wrong?"

"What is out there, Earl? What do I face?"

"The city. You have seen-faced it before." Curious, he added, "Can you krang the wall?"

"The wall? No. There is only something-" She broke off, shivering. "Something I don't understand. It isn't familiar, Earl. I don't like it."

"The wall, Embira." He took her head between his hands and guided her sightless eyes along its length. "Can you isolate it as you can the hull?" He frowned at her answer. "No?"

"No, Earl. But there is something there." She pointed with her arm. "I can krang it. It isn't like what lies beyond." She added uncertainly, "I can't remember it being there before."

A manifestation of the triple suns? If so, time was limited, there was no way of knowing when all three would be in the sky at the same time again. A mistake? If so, nothing could be lost by trying.

Back at the ship Marek said incredulously, "A door? Earl, are you sure?"

"No, but it's worth the chance. Embira spotted something, an alteration. We must investigate. Get the others and follow."

"But-"

"Hurry! The red sun's setting. Once it has gone the chance could be lost!"

A chance which seemed less possible the closer they approached the wall. It hadn't changed. At close hand it seemed as firm and as unbroken as before. To normal eyes, at least, but Embira lacked normal vision. Walking steadily in the lead she made directly toward a certain point. Dumarest, Usan Labria cradled in his left arm, followed. From the rear of the little column the engineer voiced his doubts.

"A door? Earl, that wall's solid. How the hell can we pass through it?"

"Walk. It's a chance, but what have we to lose? Embira will guide us. Touch the one in front, close your eyes, and follow." Dumarest set the example, resting his free hand on the girl's shoulder. Behind him Pacula sucked in her breath and he felt the touch of her hand.

"Like this, Earl?"

"Yes. All in contact? Then close your eyes."

The dirt underfoot was smooth, there was no danger of stumbling, and Dumarest made a conscious effort to forget the presence of the wall. It didn't exist. Nothing existed aside from the warmth of the flesh beneath his hand, the body of the girl in the lead. The blind leading the blind-but she had her talent, and without vision, they were more crippled than she.