Leithgow maintained his chieflaboratory on the dangerous Satellite III. Other planets might haveoffered more friendly locations, but III possessed stores ofaccessible minerals valuable to the scientist's varied work, and itsposition in the solar system was most convenient, being roughlyhalfway between Earth and the outermost frontiers. Leithgow hadcounterbalanced the inherent peril of the laboratory's location byingenious camouflage, intricate defenses and hidden undergroundentrances; had, indeed, hidden it so well that none of the scavengersand brigands and more personal enemies who infested Port o' Pornoremotely suspected that his headquarters was on the satellite at all.Ships, men, could pass over it a score of times with never an inklingthat it lay below.

  After a short silence, Eliot Leithgow began his explanation.

  "You'll remember," he told the intent Hawk, "that Ku Sui's menkidnapped me from our friend Kurgo's house in Porno. There were fiveof them: robot-coolies. They took us entirely by surprise, and killedKurgo and bore me to Ku Sui's asteroid.

  "Well, I had come to Kurgo's house in the first place to arrange forsupplies for building an addition to my laboratory, and I had with mea sheaf of papers containing plans for this addition. The plans arenot important; they tell nothing--but there was a figure on one of thepapers that might reveal everything! The figure 5,576.34. Do you knowwhat that stands for?"

  The adventurer thought for a moment, then shook his head. Leithgownodded. He went on:

  "Few would. _But among the few would be Ku Sui!_

  "You'll remember that on building my laboratory we considered itextremely important to have it on the other side of the globe fromPort o' Porno--diametrically opposite--so that the movements of ourships to and from it would be hidden from that pirate port.Diametrically opposite--remember? Well, the diameter of Satellite IIIis 3,550 miles. This diameter multiplied by 3.1416 gives 11,152.63miles as the circumference, and one half the circumference is 5,576.34miles--the exact distance of my laboratory from Port o' Porno!"

  "I see," Carse murmured. "I see."

  "That figure meant nothing to you, nor would it to the average person;but to a mathematician and astronomer--to Dr. Ku Sui--it would be achallenge! He would be studying the paper on which it is written down.One of Eliot Leithgow's papers. Plans for an addition to a laboratory.Therefore, Eliot Leithgow's laboratory. And then the figure: half thecircumference of Satellite III. Why, he would at once deduce that itgave the precise location of my laboratory!"

  * * * * *

  The Hawk rose quickly. "If those papers fell into Dr. Ku's hands--"

  "He would know exactly where the laboratory is," Leithgow finished."He would search. Its camouflage would not hold him long. And thatwould be the end of my laboratory--and us too, if we were caughtinside."

  "Yes," snapped the Hawk. "You imply that the papers were left inKurgo's house?"

  "I had them in the bottom drawer of the clothes-chest in the room Ialways use. The coolies did not take them. At that time they wantednothing but me."

  Friday, rubbing his woolly crown, interjected: "But, even if Ku Sui'sstill alive, he wouldn't know about them papers. Far's _I_ can see,they're safe."

  "No!" Leithgow cried. "That's it! They're not! Follow it logically,point by point. Assuming that Dr. Ku's alive, he has one point ofcontact with us--Kurgo's house, in Porno, where I was kidnapped. Hewants us badly. He will anticipate that one of us will go back to thathouse: to care for Kurgo's body, to get my belongings--for severalreasons. So he will radio down--he probably can't come himself--forhenchmen to station themselves at the house and to ransack itthoroughly for anything pertaining to me. The papers would fall intotheir hands!"

  "All right," said Carse levelly. "We must get those papers. They willeither be still in the house or in the possession of Dr. Ku's men atPorno. But whichever it is--_we must get them before Ku Sui does_." Hepaused.

  "Well," he said, "that means me." He turned and looked down at the oldman and smiled. "There's no use risking the three of us. I'll go toKurgo's house myself."

  "If the papers are gone, suh?" asked Friday.

  "I don't know. What I do will depend on what I discover there."

  "But," said Leithgow, "there may be guards! There may be an ambush!"

  "I have a powerful weapon. M. S. Unknown, so far; new to SatelliteIII. Ku Sui himself supplied it. This space-suit."

  * * * * *

  The Hawk scanned the "western" sky and began giving brisk orders.

  "Eliot, you've got to go to some place of safety until this is allover. You too, Eclipse, to take care of him. Let me see.... There'sCairnes, and Wilson.... Wilson's the one. He should be at his ranchnow. You remember it: Ban Wilson's ranch, on the Great Briney Lake?Right. Both of you will go there and wait. I'll meet you there whenI'm finished. And at that time I'll either have the papers or knowthat Ku Sui has found the laboratory."

  Again on his feet, the old Master Scientist regarded anxiously thisslender, coldly calculating man who was his closest friend. He wasafraid. "Carse," he said, "you're going back alone into probabledanger. The papers--the laboratory--they're important--but not soimportant as your life."

  There was visible now in the Hawk's face that hard, unflinchingwill-to-do that had made him the spectacular adventurer that he was."Did you ever know me to run from danger?" he asked softly. "Did youever know me to run from Ku Sui?..." And Eliot Leithgow knew that thecourse was set, no matter what it might hold.

  Carse again glanced at Jupiter, hanging massive in the blue overhead."About three hours of daylight left," he observed. "Now, closeface-plates. We must go up--far up--to get our bearings."

  Altitude swept back the horizon as they arrowed up through the warm,glowing air. From far in the heavens, perhaps twenty miles, Carse sawwhat he looked for--a bright gleam of silver in the monochrome of theterrain, where Jupiter's light struck on the smooth metal hides of agroup of space-ships resting in the satellite's lone port, Porno.Eighty, a hundred miles away--some such distance. Into the helmet'stiny microphone he said:

  "That's Porno, over to the 'north,' and there to one side is the GreatBriney. It's not far: you won't have to hurry, Eliot. Head straightfor the lake and follow the near shoreline toward Porno, and you'llcome to Ban Wilson's ranch. Now we part."

  The three clinging, giant forms separated. The direction-rods forhorizontal movement were out-hinged. A last touch of mitten-gloves onthe bloated suits fabric; a nod and a smile through the face-plates;and a few parting words:

  "Good luck, old comrade!"--in Leithgow's soft voice; and the Negro'sdeep, emphatic bass: "Don't know how far these little sets work, suh,but if you need me, call. I'll keep listenin'!"

  And then white man and black were speeding away in the ruddy flood ofJupiter-light, and Hawk Carse faced the danger trail alone, as was hiswont.

  * * * * *

  Caution rather than speed had to mark his journey, Carse knew. Severalranches lay scattered in the jungle smother between him and theport--stations where the weed isuan was collected and refined into thedeadly finished product. They were worked for the most part byVenusians allied with Ku Sui: the Eurasian practically controlled thedrug trade; and therefore, if any alarm had been broadcast, many menwould already be on the lookout for him.

  So the Hawk dropped low, and chose a course through the screeningwalls of the jungle. It did not take him long to attain full masteryof the suit's controls, and soon he was gliding cleanly through thehollows created by the mammoth outthrusting treetops in a course crazyand twisted, but one which kept him pointing always towards Porno.Presently he found an easier highway and a faster--a sluggish, dirtyyellow stream, quite broad, which ended, he was sure, in a swampwithin a mile of his destination.

  Flanked by the jungle growth which sprouted thickly from each bank, agray, ghostly shape in the shadows lying over the water, he spedthrough the dying afternoon. He kept at least ten feet above thesurface, well out of reach of such water beasts as from time t
o timereared up through the placid surface to scan him. Once a huge gantor,gulping a drink from the bank, snorted and went trumpeting away at thegrotesque sight of him--flying without wings!--and once too, on risingcautiously above the treetops to reconnoiter, Carse saw life far moreperilous to him: a small party of men, stooping over a swamp-brink andplucking the ripe isuan weed. At this he dived steeply and fled on;and he knew he had gone unobserved, for there came no outcry ofdiscovery from behind.

  * * * * *

  Jupiter lowered its murky disk as the miles streamed past, breeding alegion of shadows welcome to the fabric-clad monster skimming throughthem and to the creatures who blinked and stirred as night approached.The stream broadened into shallow pockets; patches of swamp appearedand absorbed the stream; and Carse knew he was close to hisdestination.

  He cut his speed and glanced around. Ahead, the dark spire of a giantsakari tree climbed into the gloom. It would be a good place. The manrose slowly; like a wraith on the wind he lifted into its top-mostbranches; and there, in the broad, cuplike leaves, he warily ensconcedhimself. For man-sounds came into his opened helmet, and through afringe of leaves, across a mile of tumbled swamp and marsh, he couldsee the guarding fences of the cosmetropolis of Porno.

  A last slice of blotched, flaming red, the rim of setting Jupiter,still silhouetted Porno, sprawled inside its high, electric-wiredfences, and the flood of fading light brushed the town with beauty.The rows of tin shacks which housed its dives, the clustered,nondescript hovels, the merchants' grim strongholds of steel--allmerged into a glowing mirage, a scene far alien to the brooding swampand savage jungle in whose breast it lay. Here and there severalspace-ships reared their sunset-gilded flanks, glittering high-lightsin the final glorious burst of Jupiter-light....

  The planet's rim vanished abruptly, and Porno returned to truecharacter.

  For a moment it appeared what it was: a blotched, disordered huddle,ugly, raw, fit companion of the swamp and jungle. Then beads of lightappeared, some still, some winking, one crooked line of flaringillumination marking the Street of the Sailors, along which thenotorious kantrans flourished, now ready for their nightly brood ofmen who sought forgetfulness in revelry. Soon, Carse knew, the faintman-noises he heard would grow into a broad fabric of sound, stitchedacross by shrieks and roars as the isuan and alkite flowed free. Andall around the lone watcher in the sakari tree the night-monsters werecrawling out in jungle and swamp on the dark routine of their livesas, in the town, two-legged creatures even lower in their degradationwent abroad after the dope and liquor which gave them their viciousrecreation.

  The night flowed thicker around him.

  * * * * *

  From somewhere behind, the Hawk heard a suck of half-fluid mud as agiant body stretched in its sleeping place. A tree close to hissuddenly fluttered with the unseen life it harbored. A hungry gantorraised its long deep bellow to the night, and another answered, andanother.

  It grew pitch black. Only a sprinkling of pin-points of light markedPorno to the eye. The sky beyond the town matched the sky to the rear.Jupiter's light now had fled the higher air levels. The time had come.

  Cautiously Carse brushed the branches aside, rose upright and pressedthe mitten switch over to repulsion. In instant response his giant'sbulk lifted lightly. He sped upward, straight and fast; and at twothousand feet, still untouched by the sinking planet's rays, hebrought himself to an approximate halt and peered below.

  Port o' Porno lay spread out beneath, one thin line of light-pricksoff which angled fainter lines, extending only a short distance andthen dying widely off. There were perhaps two thousand men in thetown--men from all the countries of the three planets inhabited bycreatures that could be called human--and of these at least threequarters knew Hawk Carse as an enemy, because of his intolerance fortheir dope-trade. His approach to the house Number 574 had to beswift, direct, unseen, unheard.

  He was able to make it so. Pointing the direction rod, he wingedforward until directly above an estimated spot, then dropped athousand feet. A pause while he searched; another drop. He knewKurgo's house well, but the scene was confusing from above, and thestreet the house was on was always dark at night.

  He made it out at last. The squat two-storied structure, similar toother merchants' strongholds, seemed unlit and unwatched. Carse swungback the hinged mittens of the suit and slid his hands out ready foraction. In his left he took his ray-gun; then, pressing themitten-switch, he dropped straight, silent, swift, like the Hawk henow truly was.

  * * * * *

  A single window-port, high up, broke the smooth rear of Kurgo's house.It faced a silent alleyway. The steel shutters were closed, but a pullswung them noiselessly outward. For a brief moment Carse's bulginggiant's figure of metal and fabric hung black against the shadowedwindow-port. The room he peered into was solid black. He heard nosound. Clumsily he thrust out and stepped in.

  Silence. Inky nothingness--but the air was weighted with many things,and among them one which brought the short hairs on the Hawk's neckprickling erect. A smell! It was not to be mistaken--a faint, but rankand fetid and altogether identifying smell--the body-smell of aVenusian!

  For a moment Hawk Carse's breathing stopped. Metal clanked on metalfor an instant as he moved from the window-port and became one withthe darkness inside; then silence again, as his eyes trained into thevault and his hand held ready on the ray-gun. He waited.

  Was it a trap? He had seen no guards watching the house; had sensed itdeserted. But the steep shutters, unlocked, readily permittingentrance--and the smell! Even if not still there, a Venusian had beenin the room, and a Venusian of Port o' Porno was an enemy. AVenusian.... There were only some sixty on the whole satellite, and,of these, fifty were the men of Lar Tantril. Lar Tantril, powerfulhenchman of Dr. Ku Sui, director of the Eurasian's drug trade onSatellite III. But that line of thought had to wait.

  "I see you!" he whispered suddenly and sharply. "My gun's on you. Comeforward!"

  * * * * *

  No answer; not the slightest sign or stir in the darkness. He breathedagain.

  Carse knew the arrangement of Kurgo's house. He was in hissecond-story sleeping-room. There was a door in the wall ahead,leading into the room Leithgow was accustomed to use on his visits,and there the papers should be. But first he would have to have light.

  His ears pitched for any betraying sound, Carse moved heavily to hisleft until a wall arrested him. He felt along it, located the desk hesought for and scoured through it. His fingers found the flash he knewwas there.

  The darkness then was slit by a hard straight line of white. It shotover the room picking out overturned chairs, a bowl that had toppledto the floor, scattering its contents of ripe akalot fruit, a sleepingcouch, its sheets and pillows awry, and--something human.

  A half-clothed body lay sprawled beside the couch, its hands thrustclutching forward and its unseeing eyes still staring at the doorwhence had come the shots that had burnt out the left side of itschest. Dead. Three days dead. The murdered master of the house, Kurgo,lying where Ku Sui's robot-coolies had shot him down.

  The Venusian-smell swept more strongly into his nostrils as theadventurer opened the door into Leithgow's room. No Venusian had everbeen in those rooms _before_ the abduction.

  Carse's light danced over the room's confusion: a laboratory tableoverturned; apparatus spilled; several chains flung around, onesplintered: mute signs of the struggle Eliot Leithgow had offered hiskidnappers.

  In a corner stood a metal chest. In the bottom drawer was theall-significant answer. Hawk Carse crossed the room and slid it open.

  The papers were gone!

  * * * * *

  Methodically Carse hunted through every drawer and corner of the room,but he found no trace of them. Every article that would be of value toan ordinary thief was left; the one thing important to Dr. Ku Sui, thesheaf of pa
pers, was missing.

  The presence of the Venusian body-smell started an important train ofthought in the Hawk's mind. It signified that the papers had beentaken by henchmen of Ku Sui, which in turn signified that Ku Sui hadsurvived the crashing of the dome and was alive and again aggressivelydangerous. But was the Eurasian already on Satellite III? Was healready in personal possession of the papers?--perhaps conducting asearch for Leithgow's laboratory?

  Or did it mean that Dr. Ku had merely radioed instructions for hisVenusian henchmen to ransack the house, take whatever pertained toLeithgow, and wait for him?

  Venusians.... There was only one logical man; and as Hawk Carsethought of him in that dark and silent house of tragedy, his righthand slowly rose to the bangs of hair over his forehead and began tostroke them....

  His bangs were an unusual style for the period; they stamped him andattracted unwanted attention; but he would wear his hair in thatfashion until he went down in death. For he had once beentrapped--trapped neatly by five men, and maltreated: one, Judd theKite, whose life had paid already for his part in the ugly business;two others whom he was not now concerned with; the fourth, Dr. Ku Sui;and the fifth--a Venusian....

  That fifth, the Venusian, was Lar Tantril, now one of Ku Sal's mostpowerful henchmen, and director of his interplanetary drugtraffic--Lar Tantril, who possessed an impregnable isuan ranch onlytwenty-five miles from Port o' Porno--_Lar Tantril, who probably haddirected the stealing of the