David Walton is a native of Pennsylvania and recipient of the 2008 Philip K. Dick Award for his first novel, Terminal Mind. His latest books, SUPERPOSITION and SUPERSYMMETRY, are quantum physics thrillers with the same mind-bending feel as films like Inception and Minority Report. He is also the author of Quintessence, a science fantasy in which the Earth is really flat, and its sequel, Quintessence Sky. You can read more about his life and work at http://www.davidwaltonfiction.com/.

Terminal Mind by David Walton

Winner of the Philip K. Dick Award for best paperback science fiction novel of the year. Years in the future, the U.S. is a splintered country. The city-state of Philadelphia is ripe for revolution. Mark McGovern, the son of a rich politician, lives in a world of expensive parties and frivolous biological mods, a sharp contrast to the poor underworld of his best friend, Darin Kinsley. When the two accidentally release a sophisticated virus called a 'slicer' into the net, Mark must try to stem the tide of casualties before the charged political situation explodes. But the slicer is more than a virus. To destroy it, Mark must first sort truth from lies, not only for himself, but for the mind of the child who holds his fate.


Even before I read the first words of this trippy take on future society I knew it would be a great story, because Terminal Mind is a recipient of the Philip K. Dick Award. It is easily one of the most creative takes on the future that I've ever read. Body modification is treated as an easy way for rich people to impress their vapid, hedonistic friends. All aspects of technology have advanced in recognizable but unexpected directions, but people? They never change. Politics, manipulation, and greed are still the most powerful forces known to man. – Joseph R. Lallo



  • "High-intensity human drama set in a thoroughly imagined and highly plausible future."

    – Book Review, Orson Scott Card's InterGalactic Medicine Show
  • "A very tangled human story about young love, societal biases, and the almost inevitable and doomed tide of violent men"

    – Darwin's Evolutions magazine
  • "An enthralling near-future scenario where body styling has become an art form and where computer hacking has progressed in a chillingly believable direction. What I love about David's fiction is that his characters are firmly grounded in a social context. In Terminal Mind, the family and interpersonal conflicts are just as intriguing as the threat to society, with outcomes that are just as uncertain."

    – Nancy Fulda, Hugo and Nebula-nominated author of "Recollection"




Daddy sent me a message. He gave me a job to do but he said don't do it yet. He said just wake up and be ready. I'm awake but there's nothing to do. He left me in the dark. He said he'd come but that was seconds and seconds ago. I can do it Daddy I really can. Let me try. Where are you Daddy?

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Mark McGovern would have traded his inheritance to escape this party. Any political event meant flashy mods and petty gossip, but this one seemed worse than most. Out here on the balcony, he found some momentary relief; the night air cooled his face, and the sliding glass door muted the sounds of the party inside. Below him, the Philadelphia Crater sparkled like a bowl of diamonds. Mark switched his eyes to a higher magnification and watched headlights chase each other up and down Broad Street.

The door slid open.

"Tenny, there you are," said his father.

Mark grimaced. Tennessee—his real name—sounded pretentious, but "Tenny", his family nickname, was even worse.

"Tenny," said his father, "there's someone I'd like you to meet."

"Yes, come here, dear," said Diane, his father's latest, a woman with no more right to call him "dear" than his landlord. Mark followed them inside.

Bejeweled and betuxed ladies and gentlemen stuffed the room, sintered into a living mosaic of high-class biological modifications. He squeezed past a woman with earlobes molded into ringlets that draped over her shoulders, past a man with violet skin, past a woman who'd traded hair for a moist moss wreathed with tiny white flowers. They all held wine glasses with wrists at the same angle. They all looked at him.

Mark flashed the requisite smile. He hated this song and dance, the perpetual games of ambition and insincerity. None of these people had any interest in him beyond the attention they could bring to themselves. He spotted his great-grandfather at the bar, his arm snaked around a woman swathed in what looked like designer plastic wrap. Great-granddad was well over a hundred now, but with regular mod treatments, he seemed to age in reverse. His choices in women had grown younger, too, though for all Mark knew, that shrink-wrapped floozy might be sixty.

Jack McGovern, Mark's father, dominated the room, a wide-shouldered giant with a ferocious smile. He was the reason Mark was here. The press expected it, his father had said. The heir-apparent to the McGovern fortune must make appearances.

Mark's father crushed him in a one-armed hug and waggled fingers at those closest. "Tenny, you know Councilman Marsh and his wife Georgette, and this is Vivian DuChamp from Panache, but this—I don't believe you've met our newest artist, Dr. Alastair Tremayne. The man's a genius. With mods obviously, but he's made a few heads turn with some of his inventions as well. Patented a process to give net mods to a fetus, if you can believe that. Teach your unborn baby to read, show him pictures of his family, monitor his health, that sort of thing. Quite a hit with the maternal crowd. But I'm sorry—Dr. Tremayne, this is my son, Tennessee."

Over two meters tall, with silver hair shimmering like Christmas tinsel, Tremayne seemed hyper; he kept bouncing on the balls of his feet. Mark wasn't impressed. Tremayne would be like all his father's new discoveries: a fad for a time, then forgotten. He noticed his younger sister, Carolina, eyeing Tremayne like a hooked fish. Another fad for her then, too.

Mark worried about Carolina. At eighteen, she had a perfect figure, clear skin, golden smart-hair that arranged itself becomingly in any weather, and the very latest in eyes. Her eyes glistened, as if constantly wet with emotion, and their color—gold—shone with a deep luster like polished wood. But mods like that attracted men who were only interested in her appearance. Or her money.

Who was this Dr. Alastair Tremayne? It was impossible to tell his age. He looked twenty-five, but he could be as much as seventy if he was good at his craft.

"Councilman McGovern!" Three men crowded Mark aside and surrounded his father. A cloud of drones hovered over each shoulder, identifying them as reporters. "Mr. McGovern, we hear you're sitting on a new revelation, some synthesis of mod and fabrique technology."

Mark's father beamed. "You won't wring any secrets from me. Come to Friday's demonstration at the South Hills construction site."

Mark caught Carolina's eye, smiled, and flicked his eyes at Tremayne. She shrugged.

Isn't he cute? she sent. The words passed from her implanted Visor to his, allowing him to hear the words in his mind.

How old is he? Mark sent back.

What does that matter?

I don't want to see my sister mistreated. There are things more important than cute.

Carolina's lips puckered into a pout. You're no fun. Stop playing the big brother.

Mark blew her a kiss, pretending it was all just banter, but he made a mental note to find out something about this Dr. Tremayne. He loved Carolina, but that didn't mean he trusted her judgment.

"...a stunning fractal filigree," Mark's father was saying, "Insouciant, yet unfeigned. Don't you think so, Tennessee?"

Mark snapped around, trying to figure out what he was supposed to be agreeing with. Everyone was staring at Diane, so he did, too. That's when he noticed her skin. It seemed to be alive. Looking closer, he saw the pigment of her skin was changing, subtly, in shifting spiral patterns. He'd never seen anything like it. How was it done? A bacterium? He couldn't look at her too long; the patterns made his eyes swim.

"Very nice," he managed.

"Very nice? It's an unrivaled tour-de-force of neoplasticism!"

Mark thought his father had probably practiced those words ahead of time for the benefit of the writer from Panache. He needed to get away from this circus.

"Come now, Tenny. You can do better than 'very nice.'" His father's goatée had turned black. Mark watched it kaleidoscope through brown and gray, then back to blond. His father's mood changed accordingly, and he laughed for the crowd. "Well, well, we can't all have taste."

"That's quite a mod you have yourself," Mark ventured, nodding at the goatée, which rippled into blue.

"That's Tremayne's work. Took two liters of celgel—it probably has more smarts than I do." Appreciative laughter. He turned to Mark. "What do you think of that?"

Mark glanced at the gaggle of cognoscenti and their sycophants, then back at his father, and decided: why not? He was twenty-four years old; he could say what he pleased.

"I think the Metropolitan Hospital ER could have made better use of it," he said.

The goatée blackened. For the first time in Mark's memory, his father opened his mouth, but nothing came out.

Dr. Tremayne spoke instead. "Idealism is so charming in the young."

Carolina said, "Daddy, leave him be. You know he has that Comber friend."

She caught Mark's eye. That's your cue, she sent.

Mark frowned, then understood. "Oh yes, Darin Kinsley," he said loudly. "I spend lots of time with him, down in the Combs."

His father's goatée turned a surprising shade of pink. "Wonderful, Mark, very nice. Now perhaps you could...ah...retire for the evening? Yes?"

Mark sighed in relief and nodded his thanks to Carolina.

You owe me one, she sent.

Out the door, he broke into a run. At the back of the house, where the arches and terraces faded into shadow, he lifted his jetvac off a hook and unfolded it into aluminum seat, handles, footrests. The vacuum motor whispered to life, lifting him off the ground. He squeezed the throttle, and the jetvac shot forward, skimming up the slope behind the house.

Finally free. Darin would have been waiting for half an hour now, and he wasn't likely to find Mark's Rimmer party a good excuse. Darin railed against Rimmers almost as often as he breathed—how they prettified themselves with technology better used to cure disease, how they controlled ninety-five percent of the resources while doing five percent of the work. Yet he refused to accept anything Mark tried to give him—even a ticket for the mag. Darin despised charity, thought it weakened those who accepted it. Once, he'd even stopped Mark from giving money to a beggar in the Combs. "Leave him some dignity," he'd said. When Mark asked if the man was expected to eat his dignity, Darin had responded, "Better to starve than to cower." It made Mark ashamed of his wealth, but what could he do?

Mark's night-vision kicked in, illuminating the top of the hill: he saw Darin first, lounging back against the hillside. Another figure hunched over Darin's telescope, and Mark recognized Praveen Kumar. He had known Praveen since they were boys; their families traveled in the same circles of society, but whereas Mark had always chafed against his family privilege, Praveen was a model son: hard-working, obedient, polite. So what was he doing here joining in a cracker's prank?

Mark touched down, refolded his jetvac, and slung it over his shoulder. Darin, spotting him, jumped up with arms spread wide.

"Prince Mark," he said. "You honor us with your presence."

Mark ignored the jibe. "What's he doing here?"

"I invited him."

"You didn't ask me," said Mark. "What if he tells someone?"

"Stop worrying," said Darin. "He'll be fine."

"This isn't exactly legal," said Mark.

"But what fun would it be if we didn't show it to anyone?"

Mark sighed. He'd long since given up on winning an argument with Darin.

"Praveen knows more astronomy than either of us," Darin continued, "and he can video the fireworks while we make them happen. Of course, I still didn't tell Praveen what's going to happen."

Mark allowed a smile. He wanted to ask what Darin had told Praveen, but by that time Praveen joined them.

In recent years, Praveen had darkened his skin and hair to accentuate his Indian heritage. A double row of lithium niobate crystals studded his brow: a state-of-the-art Visor that rivaled Mark's own.

"And here's the genius in person," said Darin. "Can you actually be seen with us, Praveen, or will your agent bill us for the time?"

"You flatter me," Praveen said in a musical Indian accent he never had when they were young.

"Nonsense. Apparently you wrote quite a paper. You deserve the praise."

Praveen waved aside the compliments, but he was obviously pleased. His physicist grandfather, Dhaval Kumar, had established some of the theoretical principles behind non-attenuating laser light, the applications of which made Visor technology and the world-wide optical network possible. Praveen, who idolized his granddad, had recently been published himself in a prominent physics journal—one of the youngest ever to do so. Most of his peers didn't recognize what a triumph it was for him.

"You brought your camera?" Mark asked him.

"Yes, of course. But for what? Darin did not tell me."

Darin crouched in the grass, ignoring the question.

He unzipped a pouch at his waist and began laying out his netmask and its sensory apparatus—a cumbersome bio-electronic interface that connected eyes, ears, and mouth to a net interface. Mark had offered, more than once, to pay for a Visor, but of course Darin wouldn't hear of it.

Mark busied himself with the telescopes. The zoom mods in his eyes were no more adequate to view an astronomical event than one of those tiny camera drones was to holograph it. He snapped a memory crystal into the back and worked to calibrate the lenses. On the far side of the crater, he could see the hydroelectric dam that provided most of the city's power shining white in the darkness. Above it, a few stars twinkled faintly.

"Had a little trouble getting here," said Darin. Something in his voice caused Mark to turn around.


"Merc at the corner of 28th and Hill," said Darin. "Almost wouldn't let me pass."

"Were you polite?"

"As a politician. I guess he didn't like the look of my telescope."

"He's just there to keep the peace."

"He wouldn't have stopped you," said Darin. "He only stopped me because I'm a Comber, not because I was doing anything wrong. Rimmers are too attached to their comfortable lifestyle—you hire mercs to protect it, and call it 'keeping the peace'."

"They're preventing violence, not causing it. That's peace-keeping in anyone's book."

"Who causes violence,citizens who stand up for their rights, or those who take them away?"

Mark let it drop. Lately, Darin argued social philosophy at any provocation. They'd been school friends long before they understood the class differences, Mark's father having chosen public school over private tutors for political reasons. Even now, Mark agreed with Darin's perspectives more than his Rimmer peers', so it frustrated him when Darin's accusative pronouns shifted from 'they' to 'you'.

"Please," said Praveen, "I must know what am I photographing. I can not set my light levels unless I can estimate intensity and contrast."

Mark glanced at Darin, who was busy louvering a sticky lens into one eye. The back of the lens bristled with tiny fibers that Darin labored to keep free of tangles., "Tell him," he said.

"It's a flare," said Mark. "A NAIL flare."

He watched, amused, as Praveen's face went through a series of confused expressions. Praveen certainly knew more than they did about the various NAIL constellations of satellites. NAIL stood for Non-Attenuating Infrared Laser, and accounted for almost all of the optical net traffic in the country. The satellites were renowned for their half-mile-wide main antennas, umbrella-like dishes coated with a reflective material. When the angles between sun, satellite, and observer were just right, a burst of sunlight was reflected: a flare, lasting up to ten seconds and reaching magnitudes between minus ten and minus twelve—much brighter than anything else in the night sky. Amateur astronomers scrambled around the world to the sites the flares were predicted to appear.

Praveen rolled his eyes. "Just because it flies over does not mean you will see a flare. I cannot believe you dragged me out here. The next good flare is not for months, and I think it is only visible from Greenland."

"Don't put that camera away," said Mark. "Darin and me, we don't like to wait for months. And Greenland's too cold."

"Ready," said Darin.

Praveen's face changed again. "You're hackers? I don't believe this."

"We're nothing of the sort," said Mark. "Hackers are criminals. Hackers break into nodes to steal or destroy. Crackers, on the other hand, are in it for fun, for the thrill of the race, for the intellectual challenge. And this," he smiled, "is a crackerjack."

"A fine distinction."

"No time to argue," said Mark. "Just man that camera."

Darin sat up, a grotesquerie of celgel-smeared fibers protruding from eyes, ears, and throat. Mark simply relaxed against the hillside and unfocused his eyes. Billions of information-laden photons, careening invisibly around him, were manipulated into coherence by the holographic crystals in his Visor. The feed from the crystals spliced directly into his optic nerve, overlaying his normal vision with the familiar icons of his net interface.

Using slight movements of his eyes, he navigated deeper into the system, found a procedure called "Connect NAIL Public Portal", and executed it. At its request for a pass-image, Mark envisioned a regular icosahedron, faces shaded blue, and it granted him access. Most people chose familiar faces for their pass-images, but Mark preferred geometric shapes. They required a good spacial mind to envision properly, reducing the chance that someone else could hack into his system.

Mark checked the satellite he was connected through, verifying it was not the one they were targeting. Wouldn't do to lose a connection before they were able to clean up. A few more queries told him the NAIL satellite now entering the eastern sky was a dedicated one for federal military use. So much the better. He opened the account directory and chose an entry. It didn't matter which, since he didn't intend to complete the call. At random, he selected a recipient at the Navy base in Norfolk, Virginia.

You there, Darin? he sent.

Right in here with you.

Mark paused. Despite his bravado out on the hill, this would be the most ambitious jack they'd ever attempted. If they crashed it, the security agents would snag their IDs, and well, the federal government didn't have much clout anymore, but it could still lock them away for a long time. But hey, where was the rush without the risk? He took a deep breath, and placed the call.

No turning back now. In order to call, the software had to access the encryption algorithm, which meant opening a socket—a data hole—into the command level. The hole would be open for less than a microsecond, but a hole was a hole.

Mark watched the process logs: account lookup...server handshake...message collation...Sensing the open socket at the precise moment, his software reacted, opening a chute to prevent it from closing normally.

Chute is holding, Darin reported, and then, Dropping caterpillar. Another cracker, one of Darin's, copied itself through the chute into the system beyond.

Mark hoped the caterpillar would be quick. Written to resemble a worm, which the security software agents fought on a daily basis, the caterpillar was bait. Thinking it was just a worm, the software agents would kill it, and the caterpillar, just before dying, would fire back crucial information about the agents to Mark and Darin.

At least, that was the plan. Mark always feared the worst: that a top-flight software agent would sniff the jack and follow the trail right back through the chute. A caterpillar had to be quick, or the risks outweighed the gain.

Anything yet? he sent.

I knew you'd snap.

Have not. I'm just falling asleep waiting for your junkware.

The caterpillar spouted a stream of data. Mark studied it to see what they would be up against. Looked like a few sentries, a strongman, and...Scan it!


A nazi. They've got a nazi. That's it, I'm collapsing the...

Keep your panties on. We've got a few seconds—drop your kevorkian.


Drop it!

Cringing, Mark obeyed.

Nazis were the most feared of security agents, but common lore said their weakness was in their strength. They were so powerful that they were equipped with fail-safes, mechanisms to put them to sleep if they started attacking friendly system code. A kevorkian played off this concept, faking data to convince the nazi it was doing serious damage. The nazi then killed itself, and would remain dead—they hoped—until a sysadmin could take a look.

Mark had written this kevorkian himself, and was proud of it, but it had never been tested against a genuine nazi. He cringed, expecting at any moment to see a surge of data that would mean disaster.

You got him, said Darin.


You got him.

Mark swallowed the acid that had been rising in his throat. Of course I did. Now jump in there and get this bird turning.

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Marie Coleson knew enough about slicers to be careful. Despite practically living here at the Norfolk anti-viral lab for the last two years, she'd never handled software so volatile. The slicer reacted unpredictably to every test, and never the same way twice.

Because it was human. Not a person—Marie refused to believe that it could genuinely think or feel emotion. But generated from a human mind, and just as complex and flexible and,well, intelligentas the original. Marie's job was to break it down, understand its inner workings, and write tools to defeat it. Fortunately, she'd caught it just as it went active on one of the city's rental memory blocks. If it had distributed copies of itself on the open net, it would have been much harder to contain.

She stood, stretched, and walked to the coffee machine. It was past nine, but that was hardly unusual. Since she'd walked into a Navy recruitment center last April, she'd spent most of her time in this tiny room, with its faded paint and ten-year-old promotional posters. In the six decades since the Conflict, the federal Navy's volunteer list had declined as rapidly as the federal government's power, so she figured they were desperate for anyone. Uncle Sam would have grown her a soldier's armored body, but by the time her turn came up, she'd proved so useful in the lab that she was assigned electronic security detail instead.

It didn't matter to Marie. Not much mattered to her anymore. Not since a flier accident two days before Christmas had killed her husband and son. Two years ago now. She mourned Keith, but didn't miss him; the marriage had been falling apart anyway. That last year, he'd rarely been home, and when he was, they'd done nothing but fight. But Samuel, little Sammy, her angel, her peanut: what could be worth doing now that he was gone?

Sometimes, late in the evening, alone in the lab like she was tonight, Marie fantasized about becoming a mother again. It wasn't impossible.The fertility treatments that had produced Sammy had left an embryo unused. It was still there at the clinic, kept in frozen possibility. But she was forty-two years old, for heavens sake. Too old to consider starting such a life.

This was her life now, this lab—fighting viruses, worms, phages, krakens. Investigating, classifying, designing anti-viruses, sometimes for twenty hours a day. Any time not required for other military duties, she spent here. It kept her mind busy, and that she desperately needed.

She sipped her coffee, staring through the faded walls into her memories of the past. She was still standing there when Pamela Rider peeked through the door. Pam worked for Navy administration in the next building over, but she stopped by whenever she could.

"Don't you ever go home?" Pam said.

"Hi, Pam."

"Or out?" Pam sat the wrong way around in a swivel chair, the backrest between her legs and her arms crossed on top. Her tan was smooth and permanent, and her elegant legs had been lengthened and tapered by regular mod treatments. In a cotton flower-print dress, she cut a striking image, making Marie feel frumpy in her plasticwear overall.

"When was the last time you saw a guy?" asked Pam.

"You know I'm not interested."

" It's been two years, Marie. Two years! It's not healthy. Leave Keith already."

"No, that's not—"

"Listen, if the guy were still alive, you'd have dropped him ages ago. Relationships don't last that long. If you ask me, three months is ideal—any less, and you've hardly gotten to the good parts, but any more, and he starts to feel like he owns you."


"Come on, I remember Keith. He wasn't worth that kind of loyalty even when he was alive."

"Seriously, it's not Keith. I just don't want to go looking for another guy now."

"It's the kid, isn't it."

"The kid," Marie echoed. Yes, it was the kid. Sammy had been born three weeks early and had never looked back. He was quick to walk, quick to talk, quick to form complete sentences. He'd loved construction vehicles and chocolate candy.

"Come out with me tonight," said Pam.

"I can't."

"Come on. This is a Navy base. They line up for miles to talk to a pretty woman, which you are. A hundred tasty slabs of manflesh, just dying to be eaten up. You'll be mobbed before you take a step."

"Are you looking at the same woman I see in the mirror?"

Pam cocked her head. "You could use some sprucing up, I won't deny it. But nothing I can't manage."

"I don't know, Pam. I'll probably work late tonight. I flagged a data spike on one of the city's rental memory blocks. Turns out it's a slicer."

"Yeah? What's a slicer?"

"It's a person. Was a person. They slice down into someone's brain, copying it neuron by neuron into a digital simulation. The original brain doesn't survive."

"Get out of town. People do that?"

"It started as an immortality technology—you know, flash your mind into crystal and live forever. But it doesn't work. The trauma's too much for the mind; it goes insane."

Such a grisly practice appalled Marie, but also fascinated her. What could ever drive a person to make a slicer? She assumed a group, one member of whom sacrificed his life for the endeavor, must create them. Terrorists, maybe, or cultists of some sort? Marie knew what it was like to wish she were dead, but she couldn't relate to that kind of commitment to a cause.

"Somehow, the people who create it can control it," she said. "I'm trying to figure out how."

"Well, finish up, and then come out with me tonight."

Marie laughed. "We're talking about a slicer, here, not some teenager's porn virus."

"Like that means anything to me."

"Tell you what. Give me an hour to run some tests and send it off to a colleague, and I'll come join you."

"One hour. Promise?"


"Don't stand me up, now. I'll hold you to it."

Half an hour later, Marie thought she had the answer, though it made her a little sick. The slicer seemed to be controlled through pleasure and pain. A little module ran separately from the main simulator, a master process that could send signals to the pleasure or pain centers of the mind. Since the slicer wasn't limited by a physical body, those sensations could be as extreme as the mind could register. It was a revolting concept, like torturing someone who was mentally handicapped.

She didn't understand the whole process, though. She needed another opinion. She decided to send the slicer out to Tommy Dungan, a fellow researcher at the army base at Fort Bragg. Transporting malicious code could be dangerous, but their dedicated NAIL satellite used isolated channels, and she trusted Dungan to keep the slicer secure once it reached his end.

Just as she logged into the NAIL system, she saw an incoming call on the lab's private channel. She answered it, but the sender had already disconnected. Wrong number, probably. Marie sent the slicer to Dungan, logged off for the day, and went out to meet Pam.

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Mark fiddled with the settings on his chute analyzer, watching for any sudden change in data rate—the online equivalent of pacing the room. His kevorkian ought to have knocked down that nazi for good, but what if a sysadmin happened to spot it and cycled it back up? If the data rate across that chute so much as hiccupped...

He looked back at the analyzer just in time. An enormous surge of data was pouring back across the chute toward him.

Abort, abort! He couldn't collapse the chute until Darin pulled out, or he would hang Darin's session inside, leaving a wealth of information for sysadmins to find and track at their leisure.

Abort! Get out of there!

Done. I'm out.

Mark opened his eyes, breathing hard. Darin tore off his netmask.

"A close one," said Darin.

"We should have been caught. That nazi had plenty of time to ID us. Plenty of time."

"Cheer up. We made it." Darin pointed to the eastern sky. "Let's enjoy the show."

While Praveen made final adjustments to the camera, Mark overlaid a corner of his vision with a digital countdown.

"Five," he said. "Four. Three. Two. One."

Several seconds passed.

"Zero," Mark said, belatedly.

The eastern sky remained dark. Darin grunted.

"What happened?" said Mark.

"Don't ask me. You did the calculations."

"The calculations were correct. We did three simulations; you know they were."

"But the bird turned! I saw the telemetry before I jumped out; it was all correct."

"I don't get it," said Mark."You mean you got it wrong?" said Praveen. "I knew I should not have come. I could have been working this evening instead of hauling all this gear up to the rim for nothing. Next time, don't..."

A brilliant flash of light leapt at them from the east. Mark opened his mouth to cheer, then shut it again. There was no way that light was from the satellite. It was too far north, and besides, it was too red.

Mark could only say, "Looks like an ex—" before he was cut off by a deafening boom that echoed off the hillside. The base of the eastern mountain seemed to be on fire.

He dialed up his vision to maximum and saw fire and smoke, and behind it, a torrent of rushing water.

"It's the dam," said Mark, disbelieving. "Someone blew up the dam."