YELLOW DOOM
Every nerve quivering, Crane inched forward. At last he stopped, his face almost against the grating, peering down into the lighted cabin. His gaze riveted on a table that stood between the bunk and a wooden crate.
On that table stood the thing he had risked his life to trail — a black metal case eighteen inches square. It had recording-dials in its face, a tiny microphone earphone, and the round diaphragm of a small loudspeaker. And inside that innocent-looking case, in its preserving serum, still lived the brain of Doctor Alph!
And Doctor Alph's brain was still speaking in that dreadful, toneless voice.
"Kill me! Please kill me-"
"Not yet, my dear Doctor," mocked the man standing in front of the braincase. "The death you crave will not come until I have completely tested this secret of yours."
That mocking man who spoke, the diabolical brain-thief and murderer, was Kark Al, the little Martian!
Crane even now could not believe his eyes. How could this little wisp of a Martian have broken men's necks with his bare hands, have withstood the fire of his beams unhurt?
It seemed impossible! Yet, somehow, it had been done. Even though Crane could not comprehend the explanation, he knew that at last he looked on the man he sought.
Kark Al's eyes were cruel pinpoints behind great spectacles. "If you have tried to deceive me," he told the brain warningly, "if you have not told me all your secret-"
"I have told you all. You have made the culture for yourself," said the brain thinly. "Kill me and release me from the torture of this horrible existence!"
Rab Crane was softly releasing the catch of the ventilator grating. He had no weapon but the club and this withered little Martian was the most resourceful and remorseless killer he had ever encountered.
He crouched in the tube, stealthily opening the grating. Then the grating came loose too suddenly and slipped from his hand, falling to the floor with a clang. Kark Al whirled-
And Rab Crane sprang! He shot out of the tube like a living projectile, propelled by a terrific effort of his hunched muscles. He landed full on the Martian just as Kark Al drew his beam-gun.
They crashed to the floor together. The Martian was cat-like in his quickness, but Crane was fighting with madness born of desperate urging, and the withered little red man was no match for the Earthman's strength.
Crane tore the gun from Kark Al's hand, broke loose from the Martian and covered him with the weapon.
"Stand still, Kark Al!" he told him. "My beams didn't seem to hurt you last night for some reason, but I think that if I fire them into your face now, you'll die."
Kark Al's enormous spectacles glittered at Crane in calm curiosity. "Crane, the Earthman," he said coolly. "It was ingenious of you to come through the ventilator. I congratulate you.
"Yes, Crane the Earthman," Rab Crane said savagely. "And I'm taking this brain, and the secret it gave you for Earth!"
* * *
The brain of Doctor Alph spoke rapidly in its toneless voice:
"That secret is not for any planet, Earthman! It means doom for the rest of the Solar System if it is ever released by any planet. You must destroy it — and destroy me!"
"What is the secret?" Crane asked tensely of the square black case, his gun held steady on the coolly smiling Martian.
"It is death itself, for all organic life it touches," the mechanical, metallic voice answered. "A new kind of bacteriophage, a strange, semi-organic microscopic life which ordinarily preys only on bacteria! Doctor Alph developed this new species, and it preys not alone on bacteria but on all organic life, expanding with incredible rapidity as it assimilates food.
"A mere pinch of this deadly new bacteriophage culture dropped on a plant would be enough to destroy rapidly all life on that planet The culture would spread like lightning, enveloping and devouring all organic matter like a flame of death running across that world. And Kark Al has a vial of the culture in his pocket! When he stole my brain, he also stole a tube of the death culture. That vial in his pocket can sweep whole worlds clean of life!"
Crane staggered beneath the dreadful revelation.
"God in heaven!" he whispered to the Martian. "And you would use that as a weapon of Mars, against other worlds?"
He thrust out his hand, his eyes blazing with the trembling fury he felt.
"Give me that vial!" he said.
A gun-muzzle abruptly prodded Crane's back and a low, clear voice said:
"No, that vial goes to me! Drop your gun!"
Dazedly Crane let the pistol fall from his hand. He turned slowly.
Lalla Dee, the Venusian girl, had silently entered the cabin door behind him and was covering both him and the Martian with a beam-pistol.
Her face was no longer that of a soft, pretty schoolgirl but was chiseled in lines of stern resolve.
"Lalla Dee!" cried Crane. "What does this mean?"
"It means, Rab Crane," she said steadily, "that just as you work for Earth, and Kark Al for Mars, I work for Venus! Yes, I'm a member of the Venusian Secret Service. Headquarters sent me on this ship at the last minute when they learned that Doctor Alph's brain had been stolen. We had been trying to get Doctor Alph's secret for ourselves, of course, and knew that the thief would try to get away on the first ship.
"I thought at first that you had the brain, but I soon saw that you didn't, that you were on the trail of it just as Kin Nilga and myself were. So I watched you, thinking you might know enough to lead me to the person who did have it. And you've done so. When you asked about the cabins tonight, I kept watch outside them."
She held out her hand to the smiling little Martian.
"The vial of culture, Kark Al," she said. "It and, that brain go back to Venus."
"Lalla Dee, you'll have to kill me before I'll let you get the culture and the brain, to be used, perhaps, against Earth!" Rab Crane cried.
"I'm sorry, Crane, really," she said. "But just as you love Earth, so do I love Venus."
"You two need not continue the useless argument," Kark Al said. "The culture and the brain go where it has always been destined that they should — to Mars."
'You think you can keep them even now, with my pistol covering you?" Lalla Dee said incredulously. "You're mad!"
Kark Al chuckled. "Your ridiculous beam-pistols! Do you think such toys are of any use when you are fighting me, Nald Arkol?"
"Nald Arkol of Mars!" Crane's exclamation of amazement was echoed by the astonishment of the girl's widened eyes, as they both stared at the withered little red man.
* * *
For they knew that they stood face to face with the most mysterious and dreaded interplanetary spy in the whole Solar System — the head of the great Martian Secret Service, the ice-hearted super-spy whom no man had ever seen but about whom every secret service man had heard terrible legends.
The little Kark Al was glittering at them amusedly.
"I see that you, have heard of me," he said. "Do you still think a stupid beam-gun is enough to fight me?"
He laughed harshly.
"No. It is time to end this little comedy. Seize them, Thoh!"
In answer to his shrill order there rose suddenly out of the wooden crate beside the table, a squat, horrible figure. It was human in shape and wore grotesquely the clothes of a man. But it was not human. It was a metal robot! A mechanical man!
The robot sprang toward Rab Crane and the Venusian girl. Lalla Dee fired at it. The beams hit the robot squarely, splashed off. It was made of some rare metal impervious to ordinary atomic beams. In the next instant it had seized Rab Crane and the girl, was holding them helpless in its huge metal arms.
"Now you know how the men in Doctor Alph's house were killed," Kark Al exclaimed triumphantly. "Also Kin Nilga, the Saturnian spy who had learned I had the brain and whom I had to kill for that reason. This robot, Thoh, whom I smuggled aboard as machinery samples, can be operated by direct order or remote control.
"And now he and I and the brain — and you two prisoners, also — are going to leave the Vulcan! A Martian naval cruiser has been secretly trailing this liner, waiting to pick me up when I leave the ship. I'm leaving now and taking you two with me. If I left you here dead, someone might read from your brains the nature of our new secret weapon. Aboard the cruiser, I'll torture valuable information from you, then destroy you completely. And then-"
The eyes of Kark Al expanded in blazing emotion that held the helpless man and girl paralyzed.
"Then the deadly culture and the secret of Doctor Alph will go to Mars. And some day ships of Mars will go forth and drop a death vial like this one on each of the other planets! We'll sweep all the rest of the Solar System clean of life. Then our people can go forth and take every world from Mercury to Pluto for ourselves. Everything — all the Universe for Mars!"
Rab Crane struggled wildly in the robot's inflexible grasp.
Then he opened his mouth to shout for help. Better anything than that Kark Al keep the secret.
"No! You do not give an alarm!" Kark Al hissed, and sprang forward with pistol raised butt foremost.
It crashed down on Crane's head in a stunning blow and the TSS man knew nothing more.
When he returned to consciousness he found himself wearing a heavy flexible metal suit. A spacesuit! Its glassite-fronted helmet was on his head and he breathed tangy oxygen from the tank inside the airtight suit.
Crane tried to rise and found that the wrists of his spacesuit were tied together. Beside him lay Lalla Dee, unconscious and similarly clad in a spacesuit, also bound. They were in one of the Vulcan's space-locks, both inner and outer doors closed.
Then Crane saw Kark Al. The Martian was getting into another spacesuit. The great robot stood motionless beside its master.
Kark Al bent over Crane finally, said coolly in his muffled voice, "Thoh got you from my cabin to this space-lock without anyone in the ship seeing us. Now we are leaving the ship!"
The Martian, once inside his suit, quickly secured a chain to his belt and tied it to the waists of the others so that he and the two prisoners and the robot formed a human chain.
* * *
Then Kark Al quickly took down from the rack beside the row of spacesuits, a hand-rocket — a small affair whose reactive push was enough to move several people in the void.
Kark Al touched a button and the outer door of the lock slid open. The air in it puffed out with a sharp sound, and they looked out into the star-gemmed blackness of space.
Rab Crane saw now that the Martian had slung from his shoulders a square, insulated case which he knew contained the brain of Doctor Alph. And as he realized that the Martian was achieving final success, he tried desperately to attack him.
But Kark Al at that moment stepped calmly out from the lock into empty space! The chain at his belt yanked Lalla Dee and Rab and the robot after him. They all floated there in space, a human chain, scraping the hull of the huge liner as it forged onward.
Kark Al's hand-rocket flashed flame, its impulse dragging them all forward. They moved outward from the liner, pulling away from its gravitational drag. The stem of the liner dwindled swiftly until only its lights were visible, and then those too vanished. The Vulcan was gone! They floated alone here in space, the Martian and his two bound, helpless prisoners and the great impassive robot, who needed no spacesuit because he did not breathe. Kark Al no longer used his hand-rocket, now that they were free of the liner. Crane knew that he was waiting for the Martian cruiser to reach them.
They turned slowly as they floated there, the immense starry firmament seeming to revolve around them. Rab glimpsed Lalla Dee's white face, conscious now, through the glassite front of her helmet. His own heart was numb with the cold of ultimate failure.
A few lights appeared against the stars in the direction opposite that in which the Vulcan had gone. The lights came closer and Rab saw they were those of a long, grim black spaceship coming slowly and cautiously through the void. The Martian cruiser that had been secretly trailing the Vulcan!
Kark Al flashed his hand-rocket three times, then repeated the signal. The Martian cruiser veered, came toward them, its bow rocket-tubes firing to brake its speed. The human chain was drawn slowly toward the cruiser by its gravitational attraction. Soon they bumped along its metal side.
Kark Al drew them toward a space lock that waited, open and ready. He jerked them inside and shut the outer door. Air hissed into the lock from storage tanks. Then the inner door of the lock opened and into it ran a half-dozen men; red-skinned, bristling-haired Martian officers in the gray uniform of their planet, and pulled them into the ship's inside.
One of them was the captain of the cruiser. Excitedly he helped Kark Al out of his spacesuit. Crane and Lalla Dee, still in their suits, lay beside the silent robot.
"Nald Arkol, did you get the great secret?" the Martian captain cried.
Kark Al's eyes flashed behind his spectacles as he answered, pointing to the square insulated case he had brought.
"Yes, I got it! The brain of Doctor Alph and his secret!"
He drew from his pocket a metal tube and took out of it a glassite vial filled with a yellow, fluffy substance.
He held it up proudly.
"Gentlemen, this is the secret that will make our planet sole master of the Solar System. This culture will destroy all life on every world, and give us all nine planets for our empire!"
The Martian officers cheered wildly, their faces flaming.
"The day of Mars has come at last!" they yelled.
* * *
Rab Crane's brain was a turmoil as he looked through his helmet at the vial Kark Al held aloft. The deadly culture — and it was in a glassite vial! The TSS man saw, in that instant, the superhuman chance to snatch eight planets from the jaws of doom!
He took that chance! With one wild upward lunge, Crane threw himself forward. His tied metal-clad hands struck the vial in Kark Al's grasp and knocked it to the floor. The glassite vial tinkled to shattered fragments.
"Gods of Mars!" screamed Kark Al as the vial broke. Then death was on him, was on them all, and those were his last words.
The fluffy yellow substance on the floor seemed to explode outward ever the Martians, expanding with the speed of light, covering them with a thick blanket of yellow fluff faster than the eye could follow.
It was the deadly bacteriophage Doctor Alph had cultivated, multiplying with the incredible speed the scientist had spoken of, devouring the flesh of the Martians like flame devouring tinder!
Kark Al and the other Martians were already indistinguishable, disintegrating mounds of yellow fluff. The stuff covered the helmets and space-suits of Rab Crane and Lalla Dee but could not penetrate through their air-tight glassite suits.
Crane brushed the yellow fluff wildly from before the eyes in his helmet, saw that the incredibly expanding bacteriophage had puffed out through the whole interior of the Martian cruiser. He could hear dim screams as every man in the ship, every atom of organic life, was fastened on and devoured by the culture.
Then, in a short while there was silence inside the cruiser. The Martians were gone, devoured. The ship held only the masses of ravening yellow life that had destroyed them!
Crane staggered close to Lalla Dee.
"Try to unbind my wrists," he said in a muffled voice, through the helmet. "But for God's sake don't open your suit in the slightest or you're doomed!"
"I'll — I'll try," said the Venusian girl shakenly.
Her trembling bound hands finally managed to undo the bonds around Crane's wrists. He unbound her, then, and released the chain that had tied them to Kark Al and the robot.
The huge robot, Thoh, still stood immobile beside them. The mechanical man's metal body had not been affected by the devouring bacteriophage, but he had received no order from his master to act, and had not moved.
Crane pushed Lalla Dee into the space-lock and told her:
"Take a hand-rocket and get as far out in space from the ship as you can. I'll be with you in a moment."
She obeyed, opening the outer door of the lock, stepping out into the void and using the hand-rocket she had picked up to propel her away from the Martian cruiser.
In a few minutes she saw Crane's space-suited figure leaping out of the space-lock, using another hand-rocket. She met him, grasped his arm as they floated together at a distance from the cruiser.
"What did you do?" she cried to him, her voice conducted to him by their touching space-suits.
"I made sure that that cruiser will never drift onto any world and loose that awful plague there," he told her. "I laid a fuse to its tanks of rocket fuel."
Even as Crane spoke, the distant Martian cruiser suddenly burst into terrific light, a destroying explosion that flamed for a moment like a new sun, then vanished.
"That destroys the plague on the cruiser," Crane told her. "Now for ourselves — the culture is smeared all over our suits."
* * *
He took his hand-rocket and with its flame carefully seared every square inch of the outside of her metal suit. Lalla Dee did the same for him. The last germs of the deadly culture had been destroyed.
"Before I laid the fuse, I used the cruiser's radio to call the Vulcan," Crane told her. "They're turning around to come back and pick us up."
"And Doctor Alph's brain perished in that explosion too?" Lalla Dee cried. "No one else will ever find the secret of that culture?"
"No one else, thank God!" said Crane. "It's a power too great for any world to have."
"I'm glad that neither of us won this game, man of the TSS!" she exclaimed. "And I'll give the Vulcan's officers an explanation that will satisfy them, without letting them know the truth."
"Look, there comes the ship now!" he said, pointing.
Far off against the solemn stars, the lights of the returning Vulcan were showing. But Rab Crane was gazing past them, toward the distant green light-speck of his own world. No one there but his Chief would ever know the danger that had threatened that smiling world — and that had been averted.
Only the Chief would ever know, and all the reward that Rab Crane would ever get from him would be a little longer, stronger handshake than usual.
But that was reward enough for a man of the TSS.