the girl with the slider egg glittering in her hair watched the bailiff lead asa graybar out of the courtroom. he recognized her as old hazeltyne's daughter harriet, no doubt come to see justice done. she didn't have the hothouse-flower look asa would have expected in a girl whose father owned the most valuable of the planetary franchises. she was not afraid to meet his eye, the eye of a judicially certified criminal. there was, perhaps, a crease of puzzlement in her brow, as if she had thought crimes were committed by shriveled, rat-faced types, and not by young biological engineers who still affected crewcuts.

tom dorr, hazeltyne's general manager, was her escort. asa felt certain, without proof, that dorr was the man who had framed him for the charge of grand theft by secreting a fresh slider egg in his laboratory. the older man stared at asa coldly as he was led out of the courtroom and down the corridor back to jail.

jumpy, asa's cellmate, took one look at his face as he was put back behind bars.

"guilty," jumpy said.

asa glared at him.

"i know, i know," jumpy said hastily. "you were framed. but what's the rap?"

"five or one."

"take the five," jumpy advised. "learn basket-weaving in a nice air-conditioned rehab clinic. a year on a changeling deal will seem a lot longer, even if you're lucky enough to live through it."

asa took four steps to the far wall of the cell, stood there briefly with his head bent and turned to face jumpy.

"nope," asa said softly. "i'm going into a conversion tank. i'm going to be a muck man, jumpy. i'm going out to jordan's planet and hunt slider eggs."

"smuggling? it won't work."

asa didn't answer. the hazeltyne company had gone after him because he had been working on a method of keeping slider eggs alive. the hazeltyne company would be happy to see him mark time for five years of so-called social reorientation. but if he could get out to jordan's planet, with his physiology adapted to the environment of that wretched world, he could study the eggs under conditions no laboratory could duplicate. he might even be able to cause trouble for hazeltyne.

his only problem would be staying alive for a year.

an interview with a doctor from the conversion corps was required for all persons who elected changeling status. the law stated that potential changelings must be fully informed of the rights and hazards of altered shape before they signed a release. the requirement held whether or not the individual, like asa, was already experienced.

by the time humanity traveled to the stars, medical biology had made it possible to regenerate damaged or deficient organs of the body. regeneration was limited only by advanced age. sometime after a man's two hundredth year his body lost the ability to be coaxed into growing new cells. a fifth set of teeth was usually one's last. as long as senescence could be staved off, however, any man could have bulging biceps and a pencil waist, if he could pay for the treatment.

until the medical associations declared such treatments unethical there was even a short fad of deliberate deformities, with horns at the temples particularly popular.

from regeneration it was a short step to specialized regrowth. the techniques were perfected to adapt humans to the dozen barely habitable worlds man had discovered. even on mars, the only planet outside earth in the solar system where the human anatomy was remotely suitable, a man could work more efficiently with redesigned lungs and temperature controls than he could inside a pressure suit. on more bizarre planets a few light-years away the advantages of changeling bodies were greater.

unfortunately for planetary development companies, hardly anyone wanted to become a changeling. high pay lured few. so a law was passed permitting a convicted criminal to earn his freedom by putting in one year as a changeling for every five years he would otherwise have had to spend in rehabilitation.

"what types of changelings do you have orders for right now, doctor?" asa asked the man assigned to his case. it would look suspicious if he asked for jordan's planet without some preliminary questions.

"four," answered the doctor.

"squiffs for new arcady. adapted for climbing the skycraper trees and with the arm structure modified into pseudo-wings or gliding. then we need spiderinos for von neumann two. if you want the nearest thing we have to earth, there's caesar's moon, where we'd just have to double your tolerance for carbon monoxide and make you a bigger and better gorilla than the natives. last, of course, there's always a need for muck men on jordan's planet."

the doctor shrugged, as if naturally no one could be expected to choose jordan's planet. asa frowned in apparent consideration of the alternatives.

"what's the pay range?" he asked.

"ten dollars a day on caesar's moon. fifteen on new arcady or von neumann two. twenty-five on jordan's."

asa raised his eyebrows.

"why such a difference? everyone knows about muck men living in the mud while they hunt slider eggs. but don't your conversions make the changeling comfortable in his new environment?"

"sure they do," said the doctor. "we can make you think mud feels better than chinchilla fur and we can have you jumping like a grasshopper despite the double gravity. but we can't make you like the sight of yourself. and we can't guarantee that a slider won't kill you."

"still," asa mused aloud, "it would mean a nice bankroll waiting at the end of the year."

he leaned forward to fill in the necessary form.

since it was cheaper to transport a normal human than to rig special environments in a spaceship, every planet operated its own conversion chambers. on the space freighter that carried him from earth asa graybar was confined to a small cabin that was opened only for a guard to bring meals and take out dirty dishes. he was still a prisoner.

sometimes he could hear voices in the passageway outside, and once one of them sounded like a woman's. but since women neither served on spaceships nor worked in the dome settlements on harsher worlds, he decided it was his imagination. he might have been dead cargo for all he learned about space travel.

nevertheless his time was not wasted. he had as a companion, or cellmate, another convict who had elected conversion to muck man. more important, his companion had done time on jordan's planet before and had wanted to return.

"it's the slider eggs," explained kershaw, the two-time loser. "the ones you see on earth knock your eyes out, but they've already begun to die. there's nothing like a fresh one. and i'm not the first to go crazy over them. when i was reconverted and got home i had nine thousand dollars waiting for me. that'll buy a two-year-old egg that flashes maybe four times a day. so i stole a new one and got caught."

asa had held a slider egg in his hand as he gazed into it. he could understand. the shell was clear as crystal, taut but elastic, while the albumen was just as clear around the sparkling network of organic filaments that served as a yolk. along these interior threads played tiny flashes of lightning, part of some unexplained process of life. electrical instruments picked up static discharges from the egg, but the phenomenon remained a mystery.

hardly anyone faced with the beauty of a slider's egg bothered to question its workings. for a few expectant moments there would be only random, fitful gleamings, and then there would be a wild coruscation of light, dancing from one filament to the next in a frenzy of brilliance.

it took about four years for a slider egg to die. beauty, rarity and fading value made the eggs a luxury item like nothing the world had ever seen. if asa had found a means of keeping them alive it would have made him wealthy at the expense of the hazeltyne monopoly.

"you know what i think?" kershaw asked. "i think those flashes are the egg calling its momma. they sparkle like a million diamonds when you scoop one out of the muck, and right away a slider always comes swooping out of nowhere at you."

"i've been meaning to ask you," asa said. "how do you handle the sliders?"

kershaw grinned.

"first you try to catch it with a rocket. if you miss you start leaping for home. all this time you're broadcasting for help, you understand. when the slider catches you, you leap up while it buries its jaws in the mud where you were just standing. you dig your claws in its back and hang on while it rolls around in the mud. finally, if the 'copter comes—and if they don't shoot off your head by mistake—you live to tell the tale."