THE MYSTERY OF DENEB IV

                         By ROBERT SILVERBERG

            _When Dave Carter tried to rescue the Denebians
           he found himself in a den of thieves. And he had
           cause to remember Shakespeare's observation: "He
                  who steals my purse steals trash."_

           [Transcriber's Note: This etext was produced from
                       Fantastic February 1957.
         Extensive research did not uncover any evidence that
         the U.S. copyright on this publication was renewed.]


The first thing that crossed Dave Carter's mind was that the SOS was
some kind of hoax. Then a fist thudded into the back of his neck, and
he knew it was worse than a hoax--it was a trap.

His knees sagged and he grabbed wildly for the side of his spaceship.
Steadying himself, he struck out with a fist.

His unknown assailant grunted. Carter's eyes widened as he discovered
he was fighting another Earthman, here on this alien world in the Deneb
system. _What the devil is this?_ Carter asked himself, as his fist
crashed into the other's stomach. _They ask me to come rescue them--and
then they jump me from behind._

The man was wearing the gray-and-gold uniform of the missing
_Vanguard_ expedition. He was a big, rangy spaceman. His eyes glittered
with a cold menace that Carter had never seen in human eyes before.

Carter reached back, grasped the rungs of the ladder behind him with
both hands, and kicked out at the other. The man crumpled backward onto
the ground. Carter ran over to him.

He put a knee on the other's chest. "Who are you?" he demanded.

No answer.

"Why'd you send out an SOS?" Carter demanded.

The other man glared coldly at him without replying.

Carter pulled him to a sitting position and slapped him, twice, hard.
"Answer me! You're from the _Vanguard_ expedition, aren't you?"

"Yes." The voice sounded steely, metallic.

"Then why'd you jump me? I picked up your SOS and came down here to
rescue you! Answer me!"

"You'll know the answers soon enough."

Carter shook his head angrily. "I want to know right now. Where are the
other members of the expedition?"

"They are here. They are all safe."

Pulling the other to his feet, Carter drew his blaster and said,
"Suppose you take me to them--right now. I want some explanation of all
this. Move!"

       *       *       *       *       *

An hour before, Carter had been in space, traveling alone from the Base
Hospital on Rigel IV toward Ophiuchus VII. He expected to spend his
period of convalescence there. Ophiuchus VII was a low-grav world set
aside as a vacation planet for recuperating invalids.

Carter had been injured in a reactor explosion aboard the Starship
_Alpha Centauri_, where he had been navigator. He came out of that
pretty lightly--radiation burns, a fractured skull, and little other
damage. Some skin grafts and a complicated titanium-plate rebuild had
his body and his skull as good as new within weeks. He was on his way
to Ophiuchus to rest up before returning to spaceline duty.

But his flight was interrupted when his detectors picked up an SOS as
he passed the Deneb system.

"SOS! SOS! General rescue call!"

It was coming over on a wide-beam cast. Carter localized it on Deneb
IV, an unexplored world, and replied, "I hear you. Who's this?"

"Survey Ship _Vanguard_. We're in trouble."

"How many are you?"

"Twelve, altogether. Urgent that you rescue us."

Carter glanced around his small ship. Its maximum capacity was fifteen;
he could just about make it. "I'll be right down," he said. "Give me
landing coordinates."

They read off a string of figures and he computed an orbit. Minutes
later, he had set his ship down in the exact spot they had selected,
only to find the planet bare of life and no Earthmen in sight.

He had looked around, puzzled. Then the rangy spaceman had struck him
from behind.

And now, Carter was following his captive through a wild, untamed
jungle, heading into some strange mystery at whose nature he could only
guess. The titanium plate in his skull was beginning to itch faintly as
he moved deeper and deeper into the jungle.

After a while, signs of inhabitation began to appear. Carter spotted
the golden hull of a spaceship towering above the trees, and touched
his guide's arm. "Is that the _Vanguard_?"

"Yes."

Behind the ship, Carter could now see a large clearing, and people
moving around in it, clad in the uniform of the Survey Division of
the Intergalactic Federation. There was a building in the background,
square and dull-gray.

A man stepped forward to meet them. He was distinguished-looking and
wore the uniform of a Squadron Leader.

"I'm Gendron," he said. "Commander of the _Vanguard_."

"The name's Dave Carter, navigator, late of Starship _Alpha Centauri_.
I picked up your SOS call."

Gendron blinked. "SOS? What SOS?"

"The one you sent out, of course," Carter replied, astonished. "I've
got it on tape back at my ship. You asked for immediate rescue, said it
was urgent. I landed, and this man here attacked me. I managed to get
him under control."

       *       *       *       *       *

Gendron looked mystified. "There's been some misunderstanding here.
We're in no trouble whatever--in fact, we're doing splendidly. As you
can see, we've erected our headquarters building, and we're settling
about to map the planet, according to instructions."

Carter frowned. "What about this man here?"

"You mean Sherman? I'm afraid I can't tell you." The Squadron Leader
turned to Carter's captive. "Did you attack this man?"

"No," Sherman said. "He jumped me first."

"That's a lie!" snapped Carter. "I came out of my ship to see where you
people were, and he hit me from behind."

Gendron glanced at him quizzically. "That's hard to believe. Sherman's
one of my most reliable men. Lieutenant Carter, I'm inclined to doubt
your entire story. Would you mind explaining yourself?"

Carter began to feel a growing sense of exasperation. "Look," he said.
"I was minding my own business when this SOS came. I'm on leave now;
I'm wasting my precious free time fooling with you people. So I picked
up your SOS, and I landed. Then this man hit me. That's all I can tell
you."

"I'm completely at a loss to clarify," said the Squadron Leader. "So
far as I know, we sent out no SOS. We're in no danger here. We haven't
even begun to complete our work. I'm sorry if we've caused you some
inconvenience."

Carter shook his head. _Maybe I'm going batty_, he thought. _Maybe that
blast aboard the_ Alpha C _juggled my brains as well as cracked my
skull. Maybe I didn't hear any SOS after all._

"Okay," he said finally. "I'll go back to my ship and blast off. Forget
the whole thing."

"That might be the best idea," Gendron agreed. "Would you want Sherman
to show you the way?"

"I think I can find it myself," Carter said. He turned and headed out
of the clearing, trying to convince himself that he still had a little
of his sanity left.

He moved about three steps. Then something struck him a ringing blow
on the back of his head, and he toppled to the ground.

       *       *       *       *       *

Carter woke, feeling as if a mountain had fallen on him. His head
ached miserably, his eyes wouldn't focus, his tongue felt thick and
sand-papery.

He tried to move his hands, and discovered that he was securely bound.
His arms were strapped together with what looked like leather thongs,
and his ankles were tied as well.

He was in a dark, windowless room--probably somewhere in the squat
building in the clearing.

He struggled to get his mind functioning again. All he could think of
was the way his head hurt.

Gendron had hit him from behind. That seemed to be the rule, on this
planet. After denying everything about the SOS, Gendron had clubbed him
when he wasn't looking. It didn't figure.

And there was that faint tickling in his skull, beside the raw pain of
the bruise. He didn't understand that either.

Carter sat up against the cold wall of the dark room, and yanked at his
bonds. They didn't give. He was trussed like a Christmas turkey--for
what?

Suddenly, he stopped moving, and listened.

Voices.

They were speaking in the same cold, metallic tones the spaceman
Sherman had used when Carter first landed.

"I don't understand it," someone said. "He walked right through the
control."

"It was peculiar, all right. He came within the sphere of radiation and
it didn't have any effect at all. Gendron had to club him or he would
have gotten away."

"We couldn't have that," the first voice said. "We need all the men we
can get for The Project."

_Project? What project?_ Carter asked himself. _What the blazes is
this, anyway?_

The voices stopped, leaving Carter alone in the darkness. Conjectures
ran through his mind, none of them adding up to anything but the
obvious fact that the Survey Squad of the _Vanguard_ was up to
something fishy.

His head still throbbed, but not as badly as before. The itchy tickling
still continued. It was--it was almost as if something were trying to
enter his mind! He fought a desperate desire to break his bonds and
rip open the front of his skull and scratch away the tickling before it
drove him insane.

_If I'm not insane already_, he thought grimly.

A light flickered somewhere in the distance, and then the door of his
cell opened. Someone came in. Carter blinked as light flooded in. It
was a few moments before he could see.

Gendron stood there.

"I see you're awake, Lieutenant Carter."

"Damned perceptive of you, Gendron. I'll bet you see I'm breathing,
too."

Gendron chuckled hollowly. "I've come to apologize for hitting you
yesterday. It was a misunderstanding."

"Oh? Like the phony SOS was a misunderstanding?"

       *       *       *       *       *

Gendron seemed to scowl. He turned and gestured to someone beyond
Carter's view, and two more men entered the cell.

"Well? How does it look?" one of them asked.

"Not so good," said Gendron. "I don't think he's under control yet. I
don't know how he can resist so well."

"You sure he's still under his own will? How can you tell?"

"He's belligerent," said Gendron. "He's the same as he was last night."

"The Khethlani never fails," said one of the two men. "How could it go
wrong?"

Carter frowned. Apparently they expected him to have been taken over by
someone or something--and he hadn't been.

"Sorry to disappoint you, Gendron. Your whatever-it-is just hasn't
taken hold."

"Very strange, Carter. We may have to kill you."

"You know the Khethlani doesn't like to lose men," one of the others
reminded Gendron. "We ought to do everything we can to bring him under
control."

Gendron nodded. "Untie his legs."

One of the men bent and unwrapped the thongs. Immediately Carter's foot
lashed out in a vicious kick that sent the other away yelling.

Gendron slapped Carter twice. Then he said, "That proves it. He's
definitely not under control. Let's take him to the Khethlani."

They shoved him roughly out of the room and down a long, winding
corridor toward a distant door. As they pushed him along, Carter felt
the itching inside his skull grow to fierce proportions, until he
could hardly bear it. The faces of his three captors became oddly
peaceful, oddly emotionless, as they drew near the door.

Gendron stepped forward and threw a switch. The door slid upward.
Carter looked in--and saw the Khethlani.

It was a pulsing mass of protoplasm some twenty feet across, floating
in a bath of some thick gray-green fluid that roiled obscenely beneath
its bulk. A single great eye stared upward from the middle of the
thing, and from the eye outward radiated corded blue bundles of
nerve-cells that formed a web running through the creature's legless
body.

[Illustration: This was the lair of the Khethlani. What dread secrets
of injustice were hidden here?]

Gendron and the other two men from the _Vanguard_ were standing as if
frozen, staring down at the Khethlani. Carter grasped the railing that
encircled the thing's pit, and held on firmly. Beating waves of thought
emanated from the Khethlani.

       *       *       *       *       *

_I control you, Earthmen. I am your master._

The thoughts washed up over Carter's brain with almost unbearable
urgency. _I am your master. You will obey me to the fullest._

Carter glanced at the three men with him. Their eyes were glassy; they
were caught in an unbreakable hypnotic current.

"You ... are ... my ... master," Gendron said slowly. The other two
repeated the phrase, parrot-like.

Carter stared down at the horror in the pit. Again the wave of thought
rolled up. _I am your master, strange one._

The force of the thing's mind overwhelmed him; he rocked dizzily, but
kept his balance. Now, he knew what had happened, why Gendron had
behaved as he did.

The _Vanguard_ had landed on unexplored Deneb IV, and the minds of its
crew of twelve had been snared by the Khethlani. It had turned them
into so many puppets.

They had set a trap for him. Evidently the Khethlani was greedy for
minds, for some purpose of its own. Somehow, Carter had avoided the
trap, had stayed free of the thing's control. Even now, at close range,
he was able to resist the powerful hypnotic command.

_I am your master_, came the statement a fourth time. _I order you to
kneel._

Carter saw Gendron and the other two looking at him. Sweat burst out
and ran down his face as he fought off the Khethlani's mental command.

"He resists," Gendron said, surprised. "He resists the Khethlani."

_I order you to kneel. Kneel or be destroyed._

Gendron began to draw forth his blaster. Carter grasped the rail more
tightly, shuddering.

There was only one thing to do. Keeping his mind shut tight against the
creature's command, he knelt slowly and bowed his head.

"You ... are ... my ... master," Carter said, in slow, solemn tones.
"I ... will ... obey ... you."

"The Khethlani has won!" Gendron exclaimed. "He's under control!"

_Rise, Earthman._

Carter rose obediently and faced the creature in the pit.

_I am now your master. You will obey everything._

"You are my master now. I will obey everything."

       *       *       *       *       *

When they were in the corridor again, Gendron yanked the switch and the
heavy metal door clanged down, shutting them off from the chamber of
the Khethlani. The Squadron Leader turned to Carter, grinning.

"Well, now you're with us. How does it feel?"

"Like being with the team again," Carter lied. "Brief me on what's
been going on here."

"There are about a dozen Khethlani, on various worlds in this sector.
One to a world. They've been that way for millions of years--it's an
ancient and very wise race."

"And where do we fit in?"

"We're busy building a thought-generator," explained Gendron. "The
Khethlani wants to set up a linkage with its brothers, and it needs our
help."

"I get it. It's a sort of thought-amplifier."

"Right. The Khethlani shows us how to build it--but he can't do it
himself. We're like his arms and legs. He works through us. It's a
tremendous job."

"How far have you gotten?"

"Just the framework," Gendron said. "That's why we're sending out that
wide-beam SOS. We need all the extra hands we can get. You're the third
one so far."

"Neat. Only it almost didn't work on me."

"I still don't understand that. You resisted incredibly well. But you
couldn't stand up to the Khethlani face-to-face."

"No," Carter said. "Of course not."

"Here we are," said Gendron. "This is what we've done on the
thought-generator so far."

He opened another door, and Carter saw a large room almost completely
filled with a complex webwork of machinery. Half a dozen Earthmen were
working busily in the far corner, soldering delicate wires together and
assembling an array of transistors.

"It's a long, slow, tough job," said Gendron. "The Khethlani's guiding
us every step of the way."

"And when it's finished--?"

"Then the twelve Khethlani will be in contact with each other. Then
they'll blend their mental powers into one super-being that will
control the universe."

       *       *       *       *       *

Carter barely repressed a shudder. "How wonderful!" he forced himself
to say.

"Yes. Wonderful." Gendron slapped him on the back. "I'm sorry we had to
rough you up, Carter, but we had to get you under control."

"I understand. When are you going to show me what I can do here?"

Gendron looked at him peculiarly for a moment, and Carter realized he
had blundered. Supposedly all orders would be coming direct from the
Khethlani.

"We won't have to show you," Gendron said. "You'll know when you're
supposed to work."

"Yes, of course," Carter said. "I see that. And I think my time is
coming now."

"Good. We're happy to have you with us."

Gendron walked away, and Carter moved stiffly toward one corner of the
room and pretended to busy himself with the tangle of equipment he
found there. Whatever this thing the Khethlani was designing was, it
was a miracle of engineering. He watched the others in the room working
busily, their minds and fingers guided by the promptings of the thing
in the pit.

It was only a matter of time before the Khethlani found out that Carter
wasn't really under control--if it didn't know already. As soon as the
Khethlani was certain, it would communicate that to Gendron and his
men, and this time they wouldn't be merciful.

He was immune to the creature's control. That was apparent.

Why? There was only one answer--the titanium plate in his head.

His skull had been crushed like paper in the reactor explosion, but the
medics on Rigel IV had painstakingly patched him together again with
a cranium fashioned mostly from thin metal. From the outside, it was
indistinguishable from the original--but the metal apparently served
as a shield against the telepathic commands of the Khethlani. It was a
logical explanation.

Then he had little time to waste. Soon, the Khethlani would discover
his bluff.

Carter would have to make his move long before then. The thin titanium
plate in his skull was all that stood between the Khethlani and its
dream of galactic conquest. He had to bank on it.

       *       *       *       *       *

Gendron was outside, in the clearing. Carter came up to him, "How are
things going, Lieutenant?"

"Just fine," Carter said. "I'll have to leave you for a few moments,
though."

"Oh? What for?"

"The Khethlani is sending me back to my ship," Carter explained. "It
thinks some of the equipment I have aboard can be built into the
generator."

"Very good," Gendron said. "That stuff can be important to us, all
right. You want someone to go with you?"

_Another test_, Lieutenant Carter thought. "Of course not! The
Khethlani is guiding me!"

"Of course, Lieutenant."

The trouble was that the Khethlani was _not_ guiding him, and it took
him several hours to find his way back to his ship. Eventually he found
it, climbed up the catwalk, and entered.

Waves of thought beat at him suddenly. He sensed hatred, anger. The
Khethlani was aware! His deception was at its end.

At this distance, though, the Khethlani's commands were just so much
tinny jangling in his mind. Methodically, Carter went about his work,
grimly adjusting the automatic pilot of the ship, computing an orbit.

It took fifteen minutes. When he was finished, he blasted off, and his
small ship rose high above the atmosphere of Deneb IV. He snapped on
his radio.

The detectors immediately picked up the SOS broadcast. Evidently the
Khethlani kept its lure out at all times. He ignored it, and began to
speak into the mike.

"Gendron! Gendron! You hear me?"

There was a crackling moment of silence, and then: "I hear you. What
are you doing, Carter?"

"Never mind that now. I want you to get all your men out of that
building and as far from the clearing as possible, right away. You get
that?"

"You're a madman, Carter. The Khethlani will put a stop to--"

"It hasn't stopped me yet. I'm warning you--get out of that building,
or you'll die with your master."

       *       *       *       *       *

He snapped off the radio. Gendron had had ample warning, and Carter had
other things to occupy his mind. The little ship was reaching the top
of its climb now, and soon it would be levelling out and plunging back
down toward the surface of the planet below.

The Khethlani's thoughts beat frantically at him.

_Ground your ship! I am your master! I am--_

_You'll be nothing in five minutes_, Carter thought fiercely. His ship
was moving downward now, back into Deneb IV's atmosphere.

It was decelerating rapidly. At ten thousand miles, Carter cut in the
automatic pilot and climbed into his ejection suit. Still the ship
plunged downward. Five thousand miles. Two thousand.

At sixty thousand feet, Carter pressed the emergency ejection stud, and
a giant cybernetic hand shoved him gently but firmly through the gaping
hatch of his ship. He was swept away, off to one side, and drifted
slowly the long distance to the ground.

The bombardment of thought from the Khethlani became almost unbearable.
The alien creature knew now that it was doomed.

"Go ahead," Carter yelled derisively. "Hypnotize my spaceship! Make it
turn around!"

He was still twenty thousand feet from the ground when a bright flare
of energy squirted forth as his ship roared into the building that
housed the Khethlani.

       *       *       *       *       *

There was just a smoking pit in the ground when Carter got there.
Everything had been totally destroyed by the crash.

And for the first time since his landing, Carter no longer felt the
itching in his mind. The Khethlani was dead.

He turned and saw a man approaching, dazed and smoke-blackened. It was
Gendron.

"Who are you?" Gendron asked uncertainly. "Where are my men? My ship?"

"You're the only one left, Commander. The others didn't get away in
time."

Quickly, Carter explained to the dazed officer, who had no recollection
of anything that had happened to him since entering the Khethlani's
sphere of power.

"That's--that's unbelievable," Gendron said.

"It's all over now." Carter glanced upward. Something bright was
circling the planet in a landing orbit.

"What's that?"

"It's a spaceship," Carter said. "Drawn in by your decoy SOS
signal--only now it's the real thing."

"Will he see us?"

"He'll see the smoke," Carter said. "He'll rescue us."

There'd be some delay now, he realized, before he got to Ophiuchus VII
for that vacation.

In fact, he might never get there, he knew now. He had a big job ahead
of him--and he was the only man in the universe qualified to do it, him
and his tin skull.

He glanced upward. The job was waiting. There were eleven more
Khethlani out there to be rooted out and destroyed.


                                THE END