So much had happened so quickly during the past hour that Dalgard had no chance to plan or even sort out impressions in his mind. He had no guess as to where this stranger, now taking some of the burden of the wounded merman from him, had sprung from. The other's clothing, the helmet covering his head were more akin to those worn by the aliens than they were to the dress of the colonist. Yet the man beneath those trappings was of the same breed as his own people. And he could not believe he was a Peaceman of Pax—all he had done here spoke against those legends of dark Terran days Dalgard had heard from childhood. But where had he come from? The only answer could be another outlaw colony ship.

"We are in the inner ways," Dalgard tried to reach the mind of the merman as they pounded on into the corridors which led from the arena. "Do you know these—" He had a faint hope that the sea man because of his longer captivity might have a route of escape to suggest.

"—down to the lower levels—" the thought came slowly, forced out by a weakening will. "Lower—levels—roads to the sea—"

That was what Dalgard had been hoping for, some passage which would run seaward and so to safety, such as he had found with Sssuri in that other city.

"What are we hunting?" the stranger broke in, and Dalgard realized that perhaps the other did not follow the mind talk. His words had an odd inflection, a clipped accent which was new.

"A lower way," he returned in the speech of his own people.

"To the right." The merman, struggling against his own weakness, had raised his head and was looking about as one who searches for a familiar landmark.

There was a branching way to the right, and Dalgard swung into it, bringing the other two after him. This was a narrow passage, and twice they brushed by sealed doors. It brought them up against a blank wall. The stranger wheeled, his odd weapon ready, for they could hear the shouts of pursuers behind them. But the merman pulled free of Dalgard and went down on the floor to dig with his taloned fingers at some depressions there.

"Open here," the thought came clearly, "then down!"

Dalgard went down on one knee, able now to see the outline of a trap door. It must be pried up. His sword-knife was gone, the spear they had given him for the arena he had dropped when he dragged the merman out of danger. He looked to the stranger. About the other's narrow hips was slung a belt from which hung pouches and tools the primitive colonist could not evaluate. But there was also a bush knife, and he reached for it.

"The knife—"

The stranger glanced down at the blade he wore in surprise, as if he had forgotten it. Then with one swift movement he drew it from its sheath and flipped it to Dalgard.

On the track behind the clamor was growing, and the colony scout worked with concentration at his task of fitting the blade into the crack and freeing the door. As soon as there was space enough, the merman's claws recklessly slid under, and he added what strength he could to Dalgard's. The door arose and fell back onto the pavement with a clang, exposing a dark pit.

"Got 'em!" the words burst from the stranger. He had pressed the firing button of his weapon. Where the passage in which they stood met the main corridor, there was an agitated shouting and then sudden silence.

"Down—" The merman had crawled to the edge of the opening. From it rose a dank, fetid smell. Now that the noise in the corridor was stilled Dalgard could hear something: the sound of water.

"How do we get down?" he questioned the merman.

"It is far, there are no climbing holds—"

Dalgard straightened. Well, he supposed, even a leap into that was better than to be taken a second time by Those Others. But was he ready for such a desperate solution?

"A long way down?" The stranger leaned over to peer into the well.

"He says so," Dalgard nodded at the merman. "And there are no climbing holds."

The stranger plucked at the front of his tunic with one hand, still holding his weapon with the other. From an opening he drew a line, and Dalgard grabbed it eagerly, testing the first foot with a sharp jerk. He had never seen such stuff, so light of weight and yet so tough. His delight reached the merman, who sat up to gaze owlishly at the coils the stranger pulled from concealment.

They used the door of the well for the lowering beam, hitching the cord about it. Then the merman noosed one end about him, and Dalgard, the door taking some of the strain, lowered him. The end of the cord was perilously close to the scout's fingers when there was a signaling pull from below, and he was free to reel in the loose line. He turned to the stranger.

"You go. I'll watch them." The other waved his weapon to the corridor.

There was some sense to that, Dalgard had to agree. He made fast the end of the cord and went in his turn into the dark, burning the palm of one hand before he was able to slacken the speed of his descent. Then he landed thigh-deep in water, from which arose an unpleasant smell.

"All right—Come—" he put full force into the thought he beamed at the stranger above. When the other did not obey, Dalgard began to wonder if he should climb to his aid. Had the aliens broken through and overwhelmed the other? Or what had happened? The rope whisked up out of his hands. And a moment later a voice rang eerily overhead.

"Clear below! Coming down!"

Dalgard scrambled out of the space under the opening, heading on into the murk where the merman waited. There was a splash as the stranger hit the stream, and the rope lashed down behind him at their united jerk.

"Where do we go from here?" The voice carried through the dark.

Scaled fingers hooked about Dalgard's right hand and tugged him on. He reached back in turn and locked grip with the stranger. So united the three splashed on through the rancid liquid. In time they came out of the first tunnel into a wider section, but here the odor was worse, catching in their throats, making them sway dizzily. There seemed to be no end to these ways, which Raf guessed were the drains of the ancient city.

Only the merman appeared to have a definite idea of where they were going, though he halted once or twice when they came to a side passage as if thinking out their course. Since the man from the arena accepted the furred one's guidance, Raf depended upon it too. Though he wondered if they would ever find their way out into the open once more.

He was startled by sudden pain as the hand leading him tightened its grip to bone-bruising force. They had stopped, and the liquid washed about them until Raf wondered if he would ever feel clean again. When they started on, they moved much more swiftly. His companions were in a hurry, but Raf was unprepared for the sight which broke as they came out in a high-roofed cavern.

There was an odd, cold light there—but that light was not all he saw. Drawn up on a ledge rising out of the contaminated stream were rows of the furred people, all sitting in silence, bone spears resting across their knees, long knives at their belts. They watched with round, unblinking eyes the three who had just come out of the side passage. The rescued merman loosened his grip on Dalgard's hand and waded forward to confront that quiet, waiting assembly. Neither he nor his fellows made any sound, and Raf guessed that they had some other form of communication, perhaps the same telepathic ability to broadcast messages which this amazing man beside him displayed.

"They are of his tribe," the other explained, sensing that Raf could not understand. "They came here to try to save him, for he is one of their Speakers-for-Many."

"Who are they? Who are you?" Raf asked the two questions which had been with him ever since the wild adventure had begun.

"They are the People-of-the-Sea, our friends, our knife brothers. And I am of Homeport. My people came from the stars in a ship, but not a ship of this world. We have been here for many years."

The mermen were moving now. Several had waded forward to greet their chief, aiding him ashore. But when Raf moved toward the ledge, Dalgard put out a restraining hand.

"Until we are summoned—no. They have their customs. And this is a party-for-war. This tribe knows not my people, save by rumor. We wait."

Raf looked over the ranks of the sea folk. The light came from globes borne by every twentieth warrior, a globe in which something that gave off phosphorescent gleams swam around and around. The spears which each merman carried were slender and wickedly barbed, the knives almost sword length. The pilot remembered the flame-throwers of the aliens and could not see any victory for the merman party.

"No, knife blade against the fire—that is not equal."

Raf started, amazed and then irritated that the other had read his thoughts so easily.

"But what else can be done? Some stand must be taken, even if a whole tribe goes down to the Great Dark because they do it."

"What do you mean?" Raf demanded.

"Is it not the truth that Those Others went across the sea to plunder their forgotten storehouse of knowledge?" countered the other. He spoke slowly as if he found difficulty in clothing thoughts with words. "Sssuri said that was why they came."

Raf, remembering what he had seen—the stripping of shelves and tables of the devices that were stored on them—could only nod.

"Then it is also true that soon they will have worse than fire with which to hunt us down. And they shall turn against your colony as they will against Homeport. For the mermen, and their own records, have taught us that it is their nature to rule, that they can live in peace only when all living things on this world are their slaves."

"My colony?" Raf was momentarily diverted. "I'm one of a spacer's crew, not the member of any colony!"

Dalgard stared at the stranger. His guess had been right. A new ship, another ship which had recently crossed deep space to find them had flown the dark wastes even as the First Elders had done! It must be that more outlaws had come to find a new home! This was wonderful news, news he must take to Homeport. Only, it was news which must wait. For the sea people had come to a decision of their own.

"What are they going to do now?" Raf asked.

The mermen were not retreating, instead they were slipping from the ledge in regular order, forming somewhat crooked ranks in the water.

Dalgard did not reply at once, making mind touch not only to ask but to impress his kinship on the sea people. They were united in a single-minded purpose, with failure before them—unless—He turned to the stranger.

"They go to war upon Those Others. He who guided us here knows also that the new knowledge they have brought into the city is danger. If an end is not put to it before they can use it, then"—he shrugged—"the mermen must retreat into the depths. And we, who can not follow them—" He made a quick, thrusting gesture as if using a knife on his own throat. "For a time Those Others have been growing fewer in number and weaker. Their children are not many and sometimes there are years when none are born at all. And they have forgotten so much. But now, perhaps they can increase once more, not only in wisdom and strength of arms, but in numbers. The mermen have kept a watch on them, content to let matters rest, sure that time would defeat them. But now, time no longer fights on our side."

Raf watched the furred people with their short spears, their knives. He recalled that rocky island where the aliens had unleashed the fire. The expeditionary force would not have a chance against that.

"But your weapons would." The words addressed to him were clear, though they had not been spoken aloud. Raf's hand went to the pocket where two more of the blast bombs rested. "And this is your battle as much as ours!"

But it wasn't his fight! Dalgard had gone too far with that suggestion. Raf had no ties on this world, the RS 10 was waiting to take him away. It was strictly against all orders, all his training, for him to become involved in alien warfare. The pilot's hand went back to his belt. He was not going to allow himself to be pushed onto anything foolish, whether this "colonist" could read his mind or not.

The first ranks of the mermen had already waded past them, heading into the way down which the escaping prisoners had come. To Raf's eyes none of them paid any attention to the two humans as they went, though they were probably in mental touch with his companion.

"You are already termed one of us in their eyes," Dalgard was careful to use oral speech this time. "When you came to our rescue in the arena they believed that you were of our kind. Do you think you can return to walk safely through the city? So"—he drew a hissing breath of surprise when the thought which leaped into Raf's mind was plain to Dalgard also—"you have—there are more of you there! But already Those Others may be moving against them because of what you have done!"

Raf who had been about to join the mermen stopped short. That aspect had not struck him before. What had happened to Soriki and the flitter, to the captain and Lablet, who had been in the heart of the enemy territory when he had challenged the aliens? It would be only logical that the painted people would consider them all dangerous now. He must get out of here, back to the flitter, try to help where unwittingly he had harmed—

Dalgard caught up with him. He had been able to read a little of what had passed through the other's mind. Though it was difficult to sort order out of the tangled thoughts. The longer he was with the stranger, the more aware he became of the differences between them. Outwardly they might appear of the same species, but inwardly—Dalgard frowned—there was something that he must consider later, when they had a thinking space. But now he could understand the other's agitation. It was very true that Those Others might turn on the stranger's fellows in retaliation for his deeds.

Together they joined the mermen. There was no talk, nothing to break the splashing sound of bodies moving against the current. As they pressed on, Raf was sure that this was not the same way they had come. And once more Dalgard answered his unspoken question.

"We seek another door into the city, one long known to these tribesmen."

Raf would gladly have run, but he could not move faster than his guides, and while their pace seemed deliberate, they did not pause to rest. The whole city, he decided, must be honeycombed with these drains. After traversing a fourth tunnel, they climbed out of the flood onto a dry passage, which wormed along, almost turning on itself at times.

Side passages ran out from this corridor like rootlets from a parent root, and small parties of mermen broke from the regiment to follow certain ones, leaving without orders or farewells. At the fifth of these Dalgard touched Raf's arm and drew him aside.

"This is our way." Tensely the scout waited. If the stranger refused, then the one plan the scout had formed during the past half-hour would fail. He still held to the hope that Raf, with what Raf carried, could succeed in the only project which would mean, perhaps not his safety nor the safety of the tribe he now marched among, but the eventual safety of Astra itself, the safety of all the harmless people of the sea, the little creatures of the grass and the sky, of his own land at Homeport. He would have to force Raf into action if need be. He did not use the mind touch; he knew now the unspoken resentment which followed that. If it became necessary—Dalgard's hands balled into fists—he would strike down the stranger—take from him—Swiftly he turned his thoughts from that. It might be easy, now that he had established mental contact with this off-worlder, for the other to pick up a thought as vivid as that.

But luckily Raf obediently turned into the side passage with the six mermen who were to attack at this particular point. The way grew narrower until they crept on hands and knees between rough walls which were not of the same construction as the larger tunnels. The smaller mermen had no difficulty in getting through, but twice Raf's equipment belt caught on projections and he had to fight his way free.

They crawled one by one into a ventilation shaft much like the one he had climbed at the Center. Dalgard's whisper reached him.

"We are now in the building which houses their sky ship."

"I know that one," Raf returned almost eagerly, glad at last to be back so close to familiar territory. He climbed up the hand-and footholds the sea-monster lamp disclosed, wishing the mermen ahead would speed up.

The grille at the head of the shaft had been removed, and the invaders arose one by one into a dim and dusty place of motionless machinery, which, by all tangible evidence, had not been entered for some time. But the cautious manner in which the sea people strung out to approach the far door argued that the same might not be true beyond.

For the first time Raf noticed that his human companion now held one of the knives of the merpeople, and he drew his stun gun. But he could not forget the flame-throwers which might at that very moment be trained upon the other side of that door by the aliens. They might be walking into a trap.

He half expected one of those disconcerting thought answers from Dalgard. But the scout was playing safe—nothing must upset the stranger. Confronted by what had to be done, he might be influenced into acting for them. So Dalgard strode softly ahead, apparently not interested in Raf.

One of the mermen worked at the door, using the point of his spear as a lever. Here again was a vista of machinery. But these machines were alive; a faint hum came from their casings. The mermen scattered, taking cover, a move copied by the two humans.

The pilot remained in hiding, but he saw one of the furred people running on as light-footedly as a shadow. Then his arm drew back, and he cast his spear. Raf fancied he could hear a faint whistle as the weapon cut the air. There was a cry, and the merman ran on, vanishing into the shadows, to return a second or two later wiping stains from his weapon. Out of their places of concealment, his fellows gathered about him. And the humans followed.

Now they were fronted by a ramp leading up, and the mermen took it quickly, their bare, scaled feet setting up a whispering echo which was drowned by the clop of Raf's boots. Once more the party was alert, ready for trouble, and taking his cue from them, he kept his stun gun in his hand.

But the maneuver at the head of the ramp surprised him. For, though he had heard no signal, all the party but one plastered their bodies back against the wall, Dalgard pulling Raf into position beside him, the scout's muscular bare arm pinning the pilot into a narrow space. One merman stood at the crack of the door at the top of the ramp. He pushed the barrier open and crept in.

Meanwhile those who waited poised their spears, all aimed at that door. Raf fingered the button on his gun to "spray" as he had when he had faced the attack of the scavengers in the arena tunnels.

There was a cry, a shout with a summons in it. And the venturesome merman thudded back through the door. But he was not alone. Two of the black guardsmen, their flamers spitting fiery death, ran behind him, and the curling lash of one of those flames almost wreathed the runner before he swung aside. Raf fired without consciously aiming. Both of the sentries fell forward, to slide limply down the ramp.

Then Dalgard pulled him on. "The way is open," he said. "This is it!" There was an excited exultation in his voice.