Within the memories of our lives gone by,

afraid to die, we learn to lie

and measure out the time in coffee spoons

In fading suns, and dying moons

—from “Aftertones” by Janis Ian

The first time they came through the neighborhood there really wasn’t much neighborhood to speak of. Widely dispersed hydrogen molecules, only two or three per cubic meter. Traces of heavier elements from long-ago supernovas. The usual assortment of dust particles, at a density of one particle every cubic mile or so. The “dust” was mostly ammonia, methane, and water ice, with some more complex molecules like benzene. Here and there these thin ingredients were pushed into eddies by light pressure from neighboring stars.

Somehow they set forces in motion. I picture it as a Cosmic Finger stirring the mix, out in the interstellar wastes where space is really flat, in the Einsteinian sense, making a whirlpool in the unimaginable cold. Then they went away.

Four billion years later they returned. Things were brewing nicely. The space debris had congealed into a big, burning central mass and a series of rocky or gaseous globes, all sterile, in orbit around it.

They made a few adjustments and planted their seeds, and saw that it was good. They left a small observer/recorder behind, along with a thing that would call them when everything was ripe. Then they went away again.

A billion years later the timer went off, and they came back.

I had a position at the American Museum of Natural History in New York City, but of course I had not gone to work that day. I was sitting at home watching the news, as frightened as anyone else. Martial law had been declared a few hours earlier. Things had been getting chaotic. I’d heard gunfire from the streets outside.

Someone pounded on my door.

“United States Army!” someone shouted. “Open the door immediately!”

I went to the door, which had four locks on it.

“How do I know you’re not a looter?” I shouted.

“Sir, I am authorized to break your door down. Open the door, or stand clear.”

I put my eye to the old-fashioned peephole. They were certainly dressed like soldiers. One of them raised his rifle and slammed the butt down on my doorknob. I shouted that I would let them in, and in a few seconds I had all the locks open. Six men in full combat gear hustled into my kitchen. They split up and quickly explored all three rooms of the apartment, shouting out, “All clear!” in brisk, military voices. One man, a bit older than the rest, stood facing me with a clipboard in his hand.

“Sir, are you Doctor Andrew Richard Lewis?”

“There’s been some mistake,” I said. “I’m not a medical doctor.”

“Sir, are you Doctor—”

“Yes, yes. I’m Andy Lewis. What can I do for you?”

“Sir, I am Captain Edgar and I am ordered to induct you into the United States Army Special Invasion Corps effective immediately, at the rank of Second Lieutenant. Please raise your right hand and repeat after me.”

I knew from the news that this was now legal, and I had the choice of enlisting or facing a long prison term. I raised my hand and in no time at all I was a soldier.

“Lieutenant, your orders are to come with me. You have fifteen minutes to pack what essentials you may need, such as prescription medicine and personal items. My men will help you assemble your gear.”

I nodded, not trusting myself to speak.

“You may bring any items relating to your specialty. Laptop computer, reference books…” He paused, apparently unable to imagine what a man like me would want to bring along to do battle with space aliens.

“Captain, do you know what my specialty is?”

“My understanding is that you are a bug specialist.”

“An entomologist, Captain. Not an exterminator. Could you give me…any clue as to why I’m needed?”

For the first time he looked less than totally self-assured.

“Lieutenant, all I know is…they’re collecting butterflies.”

They hustled me to a helicopter. We flew low over Manhattan. Every street was gridlocked. All the bridges were completely jammed with mostly abandoned cars.

I was taken to an air base in New Jersey and hurried onto a military jet transport that stood idling on the runway. There were a few others already on board. I knew most of them; entomology is not a crowded field.

The plane took off at once.

There was a colonel aboard whose job was to brief us on our mission, and on what was thus far known about the aliens: not much was really known that I hadn’t already seen on television.

They had appeared simultaneously on seacoasts worldwide. One moment there was nothing, the next moment there was a line of aliens as far as the eye could see. In the western hemisphere the line stretched from Point Barrow in Alaska to Tierra del Fuego in Chile. Africa was lined from Tunis to the Cape of Good Hope. So were the western shores of Europe, from Norway to Gibraltar. Australia, Japan, Sri Lanka, the Philippines, and every other island thus far contacted reported the same thing: a solid line of aliens appearing in the west, moving east.

Aliens? No one knew what else to call them. They were clearly not of Planet Earth, though if you ran into a single one, there would be little reason to think them very odd. Just millions and millions of perfectly ordinary people dressed in white coveralls, blue baseball caps, and brown boots, within arm’s reach of each other.

Walking slowly toward the east.

Within a few hours of their appearance someone on the news had started calling it the Line, and the creatures who were in it Linemen. From the pictures on the television they appeared rather average and androgynous.

“They’re not human,” the colonel said. “Those coveralls, it looks like they don’t come off. The hats, either. You get close enough, you can see it’s all part of their skin.”

“Protective coloration,” said Watkins, a colleague of mine from the Museum. “Many insects adapt colors or shapes to blend with their environment.”

“But what’s the point of blending in,” I asked, “if you are made so conspicuous by your actions?”

“Perhaps the ‘fitting in’ is simply to look more like us. It seems unlikely, doesn’t it, that evolution would have made them look like…”

“Janitors,” somebody piped up.

The colonel was frowning at us.

“You think they’re insects?”

“Not by any definition I’ve ever heard,” Watkins said. “Of course, other animals adapt to their surroundings, too. Arctic foxes in winter coats, tigers with their stripes. Chameleons.”

The colonel mulled this for a moment, then resumed his pacing.

“Whatever they are, bullets don’t bother them. There have been many instances of civilians shooting at the aliens.”

Soldiers, too, I thought. I’d seen film of it on television, a National Guard unit in Oregon cutting loose with their rifles. The aliens hadn’t reacted at all, not visibly…until all the troops and all their weapons just vanished, without the least bit of fuss.

And the Line moved on.

We landed at a disused-looking airstrip somewhere in northern California. We were taken to a big motel, which the Army had taken over. In no time I was hustled aboard a large Coast Guard helicopter with a group of soldiers—a squad? a platoon?—led by a young lieutenant who looked even more terrified than I felt. On the way to the Line I learned that his name was Evans, and that he was in the National Guard.

It had been made clear to me that I was in charge of the overall mission and Evans was in charge of the soldiers. Evans said his orders were to protect me. How he was to protect me from aliens who were immune to his weapons hadn’t been spelled out.

My own orders were equally vague. I was to land close behind the Line, catch up, and find out everything I could.

“They speak better English than I do,” the colonel had said. “We must know their intentions. Above all, you must find out why they’re collecting…” and here his composure almost broke down, but he took a deep breath and steadied himself.

“Collecting butterflies,” he finished.

We passed over the Line at a few hundred feet. Directly below us individual aliens could be made out, blue hats and white shoulders. But off to the north and south it quickly blurred into a solid white line vanishing in the distance, as if one of those devices that make chalk lines on football fields had gone mad.

Evans and I watched it. None of the Linemen looked up at the noise. They were walking slowly, all of them, never getting more than a few feet apart. The terrain was grassy, rolling hills, dotted here and there with clumps of trees. No man-made structures were in sight.

The pilot put us down a hundred yards behind the Line.

“I want you to keep your men at least fifty yards away from me,” I told Evans. “Are those guns loaded? Do they have those safety things on them? Good. Please keep them on. I’m almost as afraid of being shot by one of those guys as I am of…whatever they are.”

And I started off, alone, toward the Line.

How does one address a line of marching alien creatures? Take me to your leader seemed a bit peremptory. Hey, bro, what’s happening…perhaps overly familiar. In the end, after following for fifteen minutes at a distance of about ten yards, I had settled on Excuse me, so I moved closer and cleared my throat. Turns out that was enough. One of the Linemen stopped walking and turned to me.

This close, one could see that his features were rudimentary. His head was like a mannequin, or a wig stand: a nose, hollows for eyes, bulges for cheeks. All the rest seemed to be painted on.

I could only stand there idiotically for a moment. I noticed a peculiar thing. There was no gap in the Line.

I suddenly remembered why it was me and not some diplomat standing there.

“Why are you collecting butterflies?” I asked.

“Why not?” he said, and I figured it was going to be a long, long day. “ You should have no trouble understanding,” he said. “Butterflies are the most beautiful things on your planet, aren’t they?”

“I’ve always thought so.” Wondering, did he know I was a lepidopterist?

“Then there you are.” Now he began to move. The Line was about twenty yards away, and through our whole conversation he never let it get more distant than that. We walked at a leisurely one mile per hour.

Okay, I told myself. Try to keep it to butterflies. Leave it to the military types to get to the tough questions: When do you start kidnapping our children, raping our women, and frying us for lunch?

“What are you doing with them?”

“Harvesting them.” He extended a hand toward the Line, and as if summoned, a lovely specimen of Adelpha bredowii fluttered toward him. He did something with his fingers and a pale blue sphere formed around the butterfly.

“Isn’t it lovely?” he asked, and I moved in for a closer look. He seemed to treasure these wonderful creatures I’d spent my life studying.

He made another gesture, and the blue ball with the Adelpha disappeared. “What happens to them?” I asked him.

“There is a collector,” he said.

“A lepidopterist?”

“No, it’s a storage device. You can’t see it because it is…off to one side.”

Off to one side of what? I wondered, but didn’t ask.

“And what happens to them in the collector?”

“They are put in storage in a place where…time does not move. Where time does not pass. Where they do not move through time as they do here.” He paused for a few seconds. “It is difficult to explain.”

“Off to one side?” I suggested.

“Exactly. Excellent. Off to one side of time. You’ve got it.”

I had nothing, actually. But I plowed on.

“What will become of them?”

“We are building a…place. Our leader wishes it to be a very special place. Therefore, we are making it of these beautiful creatures.”

“Of butterfly wings?”

“They will not be harmed. We know ways of making…walls in a manner that will allow them to fly freely.”

I wished someone had given me a list of questions.

“How did you get here? How long will you stay?”

“A certain…length of time, not a great length by your standards.”

“What about your standards?”

“By our standards…no time at all. As to how we got here…have you read a book entitled Flatland ?”

“I’m afraid not.”

“Pity,” he said, and turned away, and vanished.

Our operation in Northern California was not the only group trying desperately to find out more about the Linemen, of course. There were Lines on every continent, and soon they would be present in every nation. They had covered many small Pacific islands in only a day, and when they reached the Eastern shores, they simply vanished, as my guide had.

News media were doing their best to pool information. I believe I got a lot of those facts before the general population, since I had been shanghaied into the forefront, but our information was often as garbled and inaccurate as what the rest of the world was getting. The military was scrambling around in the dark, just like everyone else.

But we learned some things:

They were collecting moths as well as butterflies, from the drabbest specimen to the most gloriously colored. The entire order Lepidoptera.

They could appear and vanish at will. It was impossible to get a count of them. Wherever one stopped to commune with the natives, as mine had, the Line remained solid, with no gaps. When they were through talking to you, they simply went where the Cheshire Cat went, leaving behind not even a grin.

Wherever they appeared, they spoke the local language, fluently and idiomatically. This was true even in isolated villages in China or Turkey or Nigeria, where some dialects were used by only a few hundred people.

They didn’t seem to weigh anything at all. Moving through forests, the Line became more of a wall, Linemen appearing in literally every tree, on every limb, walking on branches obviously too thin to bear their weight and not even causing them to bend. When the tree had been combed for butterflies, the crews vanished, and appeared in another tree.

Walls meant nothing to them. In cities and towns nothing was missed, not even closed bank vaults, attic spaces, closets. They didn’t come through the door, they simply appeared in a room and searched it. If you were on the toilet, that was just too bad.

Any time they were asked about where they came from, they mentioned that book, Flatland. Within hours the book was available on hundreds of Web sites. Downloads ran to the millions.

The full title of the book was Flatland: A Romance of Many Dimensions. It was supposedly written by one Mr. A. Square, a resident of Flatland, but its actual author was Edwin Abbott, a nineteenth century cleric and amateur mathematician. A copy was waiting for me when we got back to camp after that first frustrating day.

The book is an allegory and a satire, but also an ingenious way to explain the concept of multidimensional worlds to the layman, like me. Mr. Square lives in a world of only two dimensions. For him, there is no such thing as up or down, only forward, backward, and side to side. It is impossible for us to really see from Square’s point of view: A single line that extends all around him, with nothing above it or below it. Nothing. Not empty space, not a black or white void…nothing.

But humans being three-dimensional, can stand outside Flatland, look up or down at it, see its inhabitants from an angle they can never have. In fact, we could see inside them, examine their internal organs, reach down and touch a Flat-lander’s heart or brain with our fingers.

In the course of the book Mr. Square is visited by a being from the third dimension, a Sphere. He can move from one place to another without apparently traversing the space between point A and point B. There was also discussion of the possibilities of even higher dimensions, worlds as inscrutable to us as the 3-D world was to Mr. Square.

I’m no mathematician, but it didn’t take an Einstein to infer that the Line, and the Linemen, came from one of those theoretical higher planes.

The people running the show were not Einstein either, but when they needed expertise they knew where to go to draft it.

Our mathematician’s name was Larry Ward. He looked as baffled as I must have looked the day before and he got no more time to adjust to his new situation than I did. We were all hustled aboard another helicopter and hurried out to the Line. I filled him in, as best I could, on the way out.

Again, as soon as we approached the Line, a spokesman appeared. He asked us if we’d read the book, though I suspect he already knew we had. It was a creepy feeling to realize he, or something like him, could have been standing…or existing, in some direction I couldn’t imagine, only inches away from me in my motel bedroom, looking at me read the book just as the Sphere looked down on Mr. A. Square.

A flat, white plane appeared in the air between us and geometrical shapes and equations began drawing themselves on it. It just hung there, unsupported. Larry wasn’t too flustered by it, nor was I. Against the background of the Line an antigravity blackboard seemed almost mundane.

The Lineman began talking to Larry, and I caught maybe one word in three. Larry seemed to have little trouble with it at first, but after an hour he was sweating, frowning, clearly getting out of his depth.

By that time I was feeling quite superfluous, and it was even worse for Lieutenant Evans and his men. We were reduced to following Larry and the Line at its glacial but relentless pace. Some of the men took to slipping between the gaps in the Line to get in front, then doing all sorts of stupid antics to get a reaction, like tourists trying to rattle the guards at the Tower of London. The Linemen took absolutely no notice. Evans didn’t seem to care. I suspected he was badly hung over.

“Look at this, Doctor Lewis.”

I turned around and saw that a Lineman had appeared behind me, in that disconcerting way they had. He had a pale blue sphere cupped in his hands, and in it was a lovely specimen of Papilio zelicaon, the Anise Swallowtail, with one blue wing and one orange wing.

“A gynandromorph,” I said, immediately, with the spooky feeling that I was back in the lecture hall. “An anomaly that sometimes arises during gametogenesis. One side is male and the other is female.”

“How extraordinary. Our…leader will be happy to have this creature existing in his…palace.”

I had no idea how far to believe him. I had been told that at least a dozen motives had been put forward by Line spokesmen, to various exploratory groups, as the rationale for the butterfly harvest. A group in Mexico had been told some substance was to be extracted—harmlessly, so they said—from the specimens. In France, a lepidopterist swore a Lineman told her the captives were to be given to fourth-dimension children, as pets. It didn’t seem all the stories could be true. Or maybe they could. Step One in dealing with the Linemen was to bear in mind that our minds could not contain many concepts that, to them, were as basic as up and down to us. We had to assume they were speaking baby talk to us.

But for an hour we talked butterflies, as Larry got more and more bogged down in a sea of equations and the troops got progressively more bored. The creature knew the names of every Lepidopteran we encountered that afternoon, something I could not claim. That fact had never made me feel inadequate before. There were around 170,000 species of moth and butterfly so far cataloged, including several thousand in dispute. Nobody could be expected to know them all…but I was sure the Linemen did. Remember, every book in every library was available to them, and they did not have to open them to read them. And time, which I had been told was the fourth dimension but now learned was only a fourth dimension, almost surely did not pass for them in the same way as it passed for us. Larry told me later that a billion years was not a formidable…distance for them. They were masters of space, masters of time, and who knew what else?

The only emotion any of them had ever expressed was delight at the beauty of the butterflies. They showed no anger or annoyance when shot at with rifles; the bullets went through them harmlessly. Even when assaulted with bombs or artillery rounds they didn’t register any emotion, they simply made the assailants and weapons disappear. It was surmised by those in charge, whoever they were, that these big, noisy displays were dealt with only because they harmed butterflies.

The troops had been warned, but there’s always some clown…

So when an Antheraea polyphemus fluttered into the air in front of a private named Paulson, he reached out and grabbed it in his fist. Or tried to; while his hand was still an inch away, he vanished.

I don’t think any of us quite credited our senses at first. I didn’t, and I’d been looking right at him, wondering if I should say something. There was nothing but the Polyphemus moth fluttering in the sunshine. But soon enough there were angry shouts. Many of the soldiers unslung their rifles and pointed them at the Line.

Evans was frantically shouting at them, but now they were angry and frustrated. Several rounds were fired. Larry and I hit the deck as a machine gun started chattering. Looking up carefully, I saw Evans punch the machine gunner and grab the weapon. The firing stopped.

There was a moment of stunned silence. I got to my knees and looked at the Line. Larry was okay, but the “blackboard” was gone. And the Line moved placidly on.

I thought it was all over, and then the screaming began, close behind me. I nearly wet myself and turned around quickly.

Paulson was behind me, on his knees, hands pressed to his face, screaming his lungs out. But he was changed. His hair was all white and he’d grown a white beard. He looked thirty years older, maybe forty. I knelt beside him, unsure what to do. His eyes were full of madness…and the name patch sewn on the front of his shirt now read:

“They reversed him,” Larry said.

He couldn’t stop pacing. Myself, I’d settled into a fatalistic calm. In the face of what the Linemen could do, it seemed pointless to worry much. If I did something to piss them off, then I’d worry.

Our Northern California headquarters had completely filled the big Holiday Inn. The Army had taken over the whole thing, this bizarre operation gradually getting the encrustation of barnacles any government operation soon acquires, literally hundreds of people bustling about as if they had something important to do. For the life of me, I couldn’t see how any of us were needed, except for Larry and a helicopter pilot to get him to the Line and back. It seemed obvious that any answers we got would come from him, or someone like him. They certainly wouldn’t come from the troops, the tanks, the nuclear missiles I’m sure were targeted on the Line, and certainly not from me. But they kept me on, probably because they hadn’t yet evolved a procedure to send anybody home. I didn’t mind. I could be terrified here just as well as in New York. In the meantime, I was bunking with Larry…who now reached into his pocket and produced a penny. He looked at it, and tossed it to me.

“I grabbed that when they were going through his pockets,” he said. I looked at it. As I expected, Lincoln was looking to the left and all the inscriptions were reversed.

“How can they do that?” I asked.

He looked confused for a moment, then grabbed a sheet of motel stationery and attacked it with one of the pens in his pocket. I looked over his shoulder as he made a sketch of a man, writing L by one hand and R by the other. Then he folded the sheet without creasing it, touching the stick figure to the opposite surface.

“Flatland doesn’t have to be flat,” he said. He traced the stick man onto the new surface, and I saw it was now reversed. “Flatlanders can move through the third dimension without knowing they’re doing it. They slide around this curve in their universe. Or, a third-dimensional being can lift them up here, and set them down here . They’ve moved, without traveling the distance between the two points.”

We both studied the drawing solemnly for a moment.

“How is Paulson?” I asked.

“Catatonic. Reversed. He’s left-handed now, his appendectomy scar is on the left, the tattoo on his left shoulder is on the right now.”

“He looked older.”

“Who can say? Some are saying he was scared gray. I’m pretty sure he saw things the human eye just isn’t meant to see…but I think he’s actually older, too. The doctors are still looking him over. It wouldn’t be hard for a fourth-dimensional creature to do, age him many years in seconds.”

“But why?”

“They didn’t hire me to find out ‘why.’ I’m having enough trouble understanding the ‘how.’ I figure the why is your department.” He looked at me, but I didn’t have anything helpful to offer. But I had a question.

“How is it they’re shaped like men?”

“Coincidence?” he said, and shook his head. “I don’t even know if ‘they’ is the right pronoun. There might be just one of them, and I don’t think it looks anything like us.” He saw my confusion, and groped again for an explanation. He picked up another piece of paper, set it on the desk, drew a square on it, put the fingertips of his hand to the paper.

“A Flatlander, Mr. Square, perceives this as five separate entities. See, I can surround him with what he’d see as five circles. Now, imagine my hand moving down, through the plane of the paper. Four circles soon join together into an elliptical shape, then the fifth one joins, too, and he sees a cross section of my wrist: another circle. Now extend that…” He looked thoughtful, then pulled a comb from his back pocket and touched the teeth to the paper surface.

“The comb moves through the plane, and each tooth becomes a little circle. I draw the comb through Flatland, Mr. Square sees a row of circles coming toward him.”

It was making my head hurt, but I thought I grasped it.

“So they…or it, or whatever, is combing the planet…”

“Combing out all the butterflies. Like a fine-tooth comb going through hair, pulling out…whaddayou call ’em…lice eggs…”

“Nits.” I realized I was scratching my head. I stopped. “But these aren’t circles, they’re solid, they look like people…”

“If they’re solid, why don’t they break tree branches when they go out on them?” He grabbed the goosenecked lamp on the desk and pointed the light at the wall. Then he laced his hands together. “You see it? On the wall? This isn’t the best light…”

Then I did see it. He was making a shadow image of a flying bird. Larry was on a roll; he whipped a grease pencil from his pocket and drew a square on the beige wall above the desk. He made the shadow-bird again.

“Mr. Square sees a pretty complex shape. But he doesn’t know the half of it. Look at my hands. Just my hands. Do you see a bird?”

“No,” I admitted.

“That’s because only one of many possible cross sections resembles a bird.” He made a dog’s head, and a monkey. He’d done this before, probably in a lecture hall.

“What I’m saying, whatever it’s using, hands, fingers, whatever shapes its actual body can assume in four-space, all we’d ever see is a three-dimensional cross section of it.”

“And that cross section looks like a man?”

“Could be.” But his hands were on his hips now, regarding the square he’d drawn on the wall. “How can I be sure? I can’t. The guys running this show, they want answers, and all we can offer them is possibilities.”

By the end of the next day, he couldn’t even offer them that.

I could see he was having tough sledding right from the first. The floating blackboard covered itself with equations again, and the…Instructor? Tutor? Translator?…stood patiently beside it, waiting for Larry to get it. And, increasingly, he was not.

The troops had been kept back, almost a quarter mile behind the Line. They were on their best behavior, as that day there was some brass with them. I could see them back there, holding binoculars, a few generals and admirals and such.

Since no one had told me to do differently, I stayed up at the Line near Larry. I wasn’t sure why. I was no longer very afraid of the Linemen, though the camp had been awash in awful rumors that morning. It was said that Paulson was not the first man to be returned in a reversed state, but it had been hushed up to prevent panic. I could believe it. The initial panics and riots had died down quite a bit, we’d been told, but millions around the globe were still fleeing before the advancing Line. In some places around the globe, feeding these migrant masses was getting to be a problem. And in some places, the moving mob had solved the problem by looting every town they passed through.

Some said that Paulson was not the worst that could happen. It was whispered that men had been “vanished” by the Line and returned everted. Turned inside out. And still alive, though not for long….

Larry wouldn’t deny it was possible.

But today Larry wasn’t saying much of anything. I watched him for a while, sweating in the sun, writing on the blackboard with a grease pencil, wiping it out, writing again, watching the Lineman patiently writing new stuff in symbols that might as well have been Swahili.

Then I remembered I had thought of something to ask the night before, lying there listening to Larry snoring in the other king-size bed.

“Excuse me,” I said, and instantly a Lineman was standing beside me. The same one? I knew the question had little meaning.

“Before, I asked, ‘Why butterflies?’You said because they are beautiful.”

“The most beautiful things on your planet,” he corrected.

“Right. But…isn’t there a second best? Isn’t there anything else, anything at all, that you’re interested in?” I floundered, trying to think of something else that might be worth collecting to an aesthetic sense I could not possibly imagine. “Scarab beetles,” I said, sticking to entomology. “Some of them are fabulously beautiful, to humans anyway.”

“They are quite beautiful,” he agreed. “However, we do not collect them. Our reasons would be difficult to explain.” A diplomatic way of saying humans were blind, deaf, and ignorant, I supposed. “But yes, in a sense. Things are grown on other planets in this solar system, too. We are harvesting them now, in a temporal way of speaking.”

Well, this was new. Maybe I could justify my presence here in some small way after all. Maybe I’d finally asked an intelligent question.

“Can you tell me about them?”

“Certainly. Deep in the atmospheres of your four gas giant planets, Jupiter, Saturn, Uranus, and Neptune, beautiful beings have evolved that…our leader treasures. On Mercury, creatures of quicksilver inhabit deep caves near the poles. These are being gathered as well. And there are life-forms we admire that thrive on very cold planets.”

Gathering cryogenic butterflies on Pluto? Since he showed me no visual aids, the image would do until something better came along.

The Lineman didn’t elaborate beyond that, and I couldn’t think of another question that might be useful. I reported what I had learned at the end of the day. None of the team of expert analysts could think of a reason why this should concern us, but they assured me my findings would be bucked up the chain of command.

Nothing ever came of it.

The next day they said I could go home, and I was hustled out of California almost as fast as I’d arrived. On my way I met Larry, who looked haunted. We shook hands.

“Funny thing,” he said. “All our answers, over thousands of years. Myths, gods, philosophers…What’s it all about? Why are we here? Where do we come from, where do we go, what are we supposed to do while we’re here? What’s the meaning of life? So now we find out, and it was never about us at all. The meaning of life is…butterflies.” He gave me a lopsided grin. “But you knew that all along, didn’t you?”

Of all the people on the planet, I and a handful of others could make the case that we were most directly affected. Sure, lives were uprooted, many people died before order was restored. But the Linemen were as unobtrusive as they could possibly be, given their mind-numbing task, and things eventually got back to a semblance of normalcy. Some people lost their religious faith, but even more rejected out of hand the proposition that there was no God but the Line, so the holy men of the world registered a net gain.

But lepidopterists…let’s face it, we were out of a job.

I spent my days haunting the dusty back rooms and narrow corridors of the museum, opening cases and drawers, some of which might not have been disturbed for decades. I would stare for hours at the thousands and thousands of preserved moths and butterflies, trying to connect with the childhood fascination that had led to my choice of career. I remembered expeditions to remote corners of the world, miserable, mosquito-bitten, and exhilarated at the same time. I recalled conversations, arguments about this or that taxonomic point. I tried to relive my elation at my first new species, Hypolimnes lewisii.

All ashes now. They didn’t even look very pretty anymore.

On the twenty-eighth day of the invasion, a second Line appeared on the world’s western coasts. By then the North American Line stretched from a point far in the Canadian north through Saskatchewan, Montana, Wyoming, Colorado, and New Mexico, reaching the Gulf of Mexico somewhere south of Corpus Christi, Texas. The second Line began marching east, finding very few butterflies but not seeming to mind.

It is not in the nature of the governmental mind to simply do nothing when faced with a situation. But most people agreed there was little or nothing to be done. To save face, the military maintained a presence following the Line, but they knew better than to do anything.

On the fifty-sixth day the third Line appeared.

Lunar cycle? It appeared so. A famous mathematician claimed he had found an equation describing the Earth-Moon orbital pair in six dimensions, or was it seven? No one cared very much.

When the first Line reached New York, I was in the specimen halls, looking at moths under glass. A handful of Line-men appeared, took a quick look around. One looked over my shoulder at the displays for a moment. Then they all went away, in their multidimensional way.

And there it is.

I don’t recall who it was that first suggested we write it all down, nor can I recall the reason put forward. Like most literate people of the Earth, though, I dutifully sat down and wrote my story. I understand many are writing entire biographies, possibly an attempt to shout out “I was here!” to an indifferent universe. I have limited myself to events from Day One to the present.

Perhaps someone else will come by, some distant day, and read these accounts. Yes, and perhaps the Moon is made of green butterflies.

It turned out that my question, that last day of my military career, was the key question, but I didn’t realize I had been given the answer.

The Lineman never said they were growing creatures on Pluto.

He said there were things they grew on cold planets.

After one year of combing the Earth, the Linemen went away as quickly as they appeared.

On the way out, they switched off the light.

It was night in New York. From the other side of the planet the reports came in quickly, and I climbed up to the roof of my building. The moon, which should have been nearing full phase, was a pale ghost and soon became nothing but a black hole in the sky.

Another tenant had brought a small TV. An obviously frightened astronomer and a confused news anchor were counting seconds. When they reached zero, a bit over twenty minutes after the events at the antipodes, Mars began to dim. In thirty seconds it was invisible.

He never mentioned Pluto as their cold-planet nursery….

In an hour and a half Jupiter’s light failed, then Saturn.

When the sun came up in America that day, it looked like a charcoal briquette, red flickerings here and there, and soon not even that. When the clocks and church bells struck noon, the Sun was gone.

Presently, it began to get cold.