Carse stood where he was, surrounded by the crystal and metal mechanisms that had no meaning for him, and knew with terrible finality that he was beaten. And now the hissing laughter broke forth on all sides, infinitely cruel and jeering.

Garach put out a trembling hand toward Hishah, “Then,” he stammered, “this is not Rhiannon?”

“Even your human mind should tell you that much now,” answered Hishah contemptuously. He had thrown back his cowl and now he moved toward Carse, his ophidian eyes full of mockery.

“By the touching of minds alone I would have known you false but even that I did not need. You, Rhiannon! Rhiannon of the Quiru, who came in peace and brotherhood to greet his children in Caer Dhu!”

The stealthy evil laughter hissed from every Dhuvian throat and Hishah threw his head back, the skin of his throat pulsing with his mirth.

“Look at him, my brothers! Hail Rhiannon, who did not know of the Veil nor why it guards Caer Dhu!”

And they hailed him, bowing low.

Carse stood very still. For the moment he had even forgotten to be afraid.

“You fool,” said Hishah. “Rhiannon hated us at the end. For at the end he learned his folly, learned that the pupils to whom he gave the crumbs of knowledge had grown too clever. With the Veil, whose secret he had taught us, we made our city impregnable even to his mighty weapons, so that when he turned finally against us it was too late.”

Carse said slowly, “Why did he turn against you?”

Hishah laughed. “He learned the use we had for the knowledge he had given us.”

Ywain came forward, one step, and said, “What was that use?”

“I think you know already,” Hishah answered. “That is why you and Garach were summoned here—not only to see this imposter unmasked but to learn once and for all your place in our world.”

His soft voice had in it now the bite of the conqueror.

“Since Rhiannon was locked in his tomb we have gained subtle dominance on every shore of the White Sea. We are few in number and averse to open warfare. Therefore we have worked through the human kingdoms, using your greedy people as our tools.

“Now we have the weapons of Rhiannon. Soon we will master their use and then we will no longer need human tools. The Children of the Serpent will rule in every palace—and we will require only obedience and respect from our subjects.

“How think you of that, Ywain of the proud head, who have always loathed and scorned us?”

“I think,” said Ywain, “that I will fall upon my own sword first.”

Hishah shrugged. “Fall then.” He turned to Garach. “And you?”

But Garach had already crumpled to the stones in a dead faint.

Hishah turned again to Carse. “And now,” he said, “you shall see how we welcome our lord!”

Boghaz moaned and covered his face with his hands. Carse gripped the futile sword tighter and asked in a strange, low voice:

“And no one ever knew that Rhiannon had finally turned against you Dhuvians?”

Hishah answered softly, “The Quiru knew but nevertheless they condemned Rhiannon because his repentance came too late. Other than they only we knew. And why should we tell the world when it pleased our humor to see Rhiannon, who hated us, cursed as our friend?”

Carse closed his eyes. The world rocked under him, and there was a roaring in his ears, as the revelation burst upon him.

Rhiannon had spoken the truth in the place of the Wise Ones. Had spoken truth when he voiced his hatred of the Dhuvians!

The hall was filled with a sound like the rustling of dry leaves as the ranks of the Dhuvians closed gently in toward Carse.

With an effort of will almost beyond human strength Carse threw open all the channels of his mind, trying desperately now in this last minute to reach inward to that strangely silent, hidden corner.

He cried aloud, “ Rhiannon!”

That hoarse cry made the Dhuvians pause. Not because of fear but because of laughter. This, indeed, was the climax of the jest!

Hishah cried, “Aye, call upon Rhiannon! Perhaps he will come from his Tomb to aid you!”

And they watched Carse out of their depthless jeering eyes as he swayed in torment.

But Ywain knew. Swiftly she moved to Carse’s side and her sword came rasping out of the sheath, to protect him as long as it could.

Hishah laughed. “A fitting pair—the princess without an empire and the would-be-god!”

Carse said again, in a broken whisper, “ Rhiannon!”

And Rhiannon answered.

From the depths of Carse’s mind where he had lain hidden the Cursed One came, surging in terrible strength through every cell and atom of the Earthman’s brain, possessing him utterly now that Carse had opened the way.

As it had been before in the place of the Wise Ones the consciousness of Matthew Carse stood aside in his own body and watched and listened.

He heard the voice of Rhiannon—the real and godlike voice that he had only copied—ring forth from his own lips in anger that was beyond human power to know.

“ Behold your Lord, oh crawling children of the Serpent! Behold—and die!”

The mocking laughter died away into silence. Hishah gave back and into his eyes came the beginning of fear.

Rhiannon’s voice rolled out, thundering against the walls. The strength and fury of Rhiannon blazed in the Earthman’s face and now his body seemed to tower over the Dhuvians and the sword was a thing of lightning in his hands.

“ What now of the touching of minds, Hishah? Probe deeply—more deeply than you did before when your feeble powers could not penetrate the mental barrier I set up against you!”

Hishah voiced a high and hissing scream. He recoiled in horror and the circle of the Dhuvians broke as they turned to seek their weapons, their lipless mouths stretched wide in fear.

Rhiannon laughed, the terrible laughter of one who has waited through an age for vengeance and finds it at last.

“ Run! Run and strive—for in your great wisdom you have let Rhiannon through your guarding Veil and death is on Caer Dhu!”

And the Dhuvians ran, writhing in the shadows as they caught up the weapons they had not thought to need. The green light glinted on the shining tubes and prisms.

But the hand of Carse, guided now by the sure knowledge of Rhiannon, had darted toward the biggest of the ancient weapons—toward the rim of the great flat crystal wheel. He set the wheel spinning.

There must have been some intricate triggering of power within the metal globe, some hidden control that his fingers touched. Carse never knew. He only knew that a strange dark halo appeared in the dim air, enclosing himself and Ywain and the shuddering Boghaz and Garach, who had risen doglike to his hands and knees and was watching with eyes that held no shred of sanity. The ancient weapons were also enclosed in that ring of dark force, and a faint singing rose from the crystal rods.

The dark ring began to expand, like a circular wave sweeping outward.

The weapons of the Dhuvians strove against it. Lances of lightning, of cold flame and searing brilliance, leaped toward it, struck—and splintered and died. Powerful electric discharges that broke themselves on the invisible dielectric that shielded Rhiannon’s circle.

Rhiannon’s ring of dark force expanded relentlessly, out and out, and where it touched the Dhuvians the cold ophidian bodies withered and shriveled and lay like cast-off skins upon the stones.

Rhiannon spoke no more. Carse felt the deadly throb of power in his hand as the shining wheel spun faster and faster on its mount and his mind shuddered away from what he could sense in Rhiannon’s mind.

For he could sense dimly the nature of the Cursed-One’s terrible weapon. It was akin to that deadly ultra-violet radiation of the Sun which would destroy all life were it not for the shielding ozone in the atmosphere.

But where the ultra-violet radiation known to Carse’s Earth science was easily absorbed, that of Rhiannon’s ancient alien science lay in uncharged octaves below the four-hundred angstrom limit and could be produced as an expanding halo that no matter could absorb. And where it touched living tissue, it killed.

Carse hated the Dhuvians but never in the world had there been such hatred in a human heart as he felt now in Rhiannon.

Garach began to whimper. Whimpering, he recoiled from the blazing eyes of the man who towered above him. Half scrambling, half running, he darted away with a sound like laughter in his throat.

Straight out into the dark ring he ran and death received him and silently withered him.

Spreading, spreading, the silent force pulsed outward. Through metal and flesh and stone it went, withering, killing, hunting down the last child of the Serpent who fled through the dark corridors of Caer Dhu. No more weapons flamed against it. No more supple arms were raised to fend it off.

It struck the enclosing Veil at last. Carse felt the subtle shock of its checking and then Rhiannon stopped the wheel.

There was a time of utter silence as those three who were left alive in the city stood motionless, too stunned almost to breathe.

At last the voice of Rhiannon spoke. “ The Serpent is dead. Let his city—and my weapons that have wrought such evil in this world—pass with the Dhuvians.”

He turned from the crystal wheel and sought another instrument, one of the squat looped metal rods.

He raised the small black thing and pressed a secret spring and from the leaden tube that formed its muzzle came a little spark, too bright for the eye to look upon, only a tiny fleck of light that settled on the stones. But it began to glow. It seemed to feed on the atoms of the rock as flame feeds on wood. Like wildfire it leaped across the flags. It touched the crystal wheel and the weapon that had destroyed the Serpent was itself consumed.

A chain-reaction such as no nuclear scientist of Earth had conceived, one that could make the atoms of metal and crystal and stone as unstable as the high-number radioactive elements.

Rhiannon said, “ Come.”

They walked through the empty corridors in silence and behind them the strange witchfire fed and fattened and the vast central hall was enveloped in its swift destruction.

The knowledge of Rhiannon guided Carse to the nerve-center of the Veil, to a chamber by the great gate, there to set the controls so that the glimmering web was forever darkened.

They passed out of the citadel and went back down the broken causeway to the quay where the black barge floated.

Then they turned, and looked back, upon the destruction of a city.

They shielded their eyes, for the strange and awful blaze had something in it of the fire of the Sun. It had raced hungrily outward through the sprawling ruins, and made of the central keep a torch that lighted all the sky, blotting out the stars, paling the low moons.

The causeway began to burn, a lengthening tongue of flame between the reeds of the marshland.

Rhiannon raised the squat looped tube again. From it, now, a dim little globule of light not a spark, flew toward the nearing blaze.

And the blaze hesitated, wavered, then began to dull and die.

The witchfire of strange atomic reaction that Rhiannon had triggered he had now damped and killed by some limiting counter-factor whose nature Carse could not dream.

They poled the barge out onto the water as the quivering radiance behind them sank and died. And then the night was dark again and of Caer Dhu there was nothing to be seen but steam.

The voice of Rhiannon spoke, once more, “ It is done ” he said. “ I have redeemed my sin.”

The Earthman felt the utter weariness of the being within him as the possession was withdrawn from his brain and body.

And then, again, he was only Matthew Carse.