They used to let me fly into Las Vegas on Fridays, for the weekend. Twenty minutes skimming just below the surface of the air before descending into the grid of neon lights that blinked and shimmered in the disappearing daylight. I always sat next to a window and watched the city appear light by light, my ears popping. There are no flights to Las Vegas anymore.

I stayed at the Tropicana. Paid for it myself because I didn't have much else to spend my paychecks on. I never really went in for lavishness, but I liked the Tropicana because in those days the casino was clean and the lobby bar always filled up with guys in suits and call girls and no one ever talked to me. Except you, of course, but that was a few years later, after I started to get used to the city and the noise and the light and I wasn't so keen on being alone anymore.

Do you remember my suite? The same suite every weekend. You only came up a few times and you seemed to match the furniture in your sequins and teased-out hair, like they'd planned it that way. I remember the first time—or maybe it was the last—you came and stood in front of the giant picture window that looked out over the city and you said, "I could drown in all that light," while I tried to fix you a martini at the wet bar. I thought that was a strange thing to say but then you were always saying strange things, and you knew how to make them sound impressive. Unlike me. I wish I could have told you the strange things I knew about—but it wasn't allowed.

You never stayed long. We watched Hawaii Five-O on the television in the bedroom and after you left I'd find trails of glitter leading from the bed into the bathroom and then out the door. In the morning I'd wake up with glitter stuck in my hair. You apologized for it, when you came up that first time. You sat down on the couch and glitter puffed up like a cloud around you, catching in the suite's track lighting. I smiled. You said, "That's the problem with me. Glitter everywhere, four nights a week."

I said, "Does it wash off easily?"

"No," you said. "I'm always finding glitter somewhere." And then you laughed at yourself.

I remember the first time you talked to me, down in the lobby bar, and there was a streak of glitter across your right cheekbone, pale gold, like a spark of electricity.

They started letting me fly out to Las Vegas when I'd been working at the base for a little under a year. I think they were worried I was going to go batty, or that I'd already started to go batty, since I worked all the time and didn't see anyone but the other researchers, the ones with the same clearance level as me—which wasn't many. I was younger than all of them, too. I think maybe my age above all else convinced them to let me out.

"We're going to let you out to breathe," said Colonel Kolansky. We were both sitting in his office, the fluorescent light buzzing faintly overhead. He folded his hands on top of his metal desk. A stack of mimeographed papers leaned over the desk's edge. I held my breath and waited for them to tip, fall, and scatter across the dusty tile floor.

The walls in his office were green, the green of my high school cafeteria. The entire compound looked like a high school cafeteria. But it smelled like the inside of an airport.

"What do you mean?" I asked. Colonel Kolansky frowned at me. "Sir," I added.

"Eh, someone up top decided it ain't that healthy. You know. Mentally speaking." Colonel Kolansky rubbed the spot on his head where his hair had started to wear thin. I used to imagine it was from all the rubbing. Now I know better. My own hair has disappeared over the years, from that same spot.

"So do I get to move off the base?" I asked. Most of the personnel here were day workers; they flew in and out every day.

"Oh, no." Colonel Kolansky held up one of his beefy hands. "No no no, you're way too important for any of that BS. No, you can get weekend leave. Assuming—" he pointed at me. "Assuming nothing else is going on. And you can only go to Vegas. No gallivanting around California."

He dismissed me then with a halfhearted flick of his hand and I went out into the hallway. I thought about Las Vegas. I'd never been. I'd never wanted to go. I thought maybe I could cheat at blackjack and stockpile money, even though I wasn't interested in money, not then and not now—just like I always told you, even though you never believed me. I still liked the idea of cheating at blackjack, though. It seemed fun, and I figured I had the brains for it. They recruited me to this place, after all.

You once asked me to tell you about my family. I hadn't known you long. We were down in the bar and you still had your costume on from that night's performance. You wore feathers in your hair, black stockings and shiny blue shoes. You brought your cocktail up to your lips after you asked, looking at me over the rim of the glass, your lids weighed down with false eyelashes. The drink glowed amber in your hand.

I changed the subject. Do you remember? I said, "My parents are dead," and then I changed the subject, because I was afraid if we talked about my family you'd start asking questions about my job again. I have always been wary of personal questions for that reason: one set of questions leads to another.

My parents really are dead, though. I didn't lie about that. They died shortly after I received my PhD, my mother first and then my father, as if he couldn't bear to live without her. It was the sort of thing he'd do, the sort of thing he'd believe in. He was a Primitive Baptist preacher. Every Sunday as a child, I sat in the little white clapboard church beside my mother, sunlight streaming in through the windows. She fanned herself with the church bulletin while my father spat out that week's sermon, all the sorts of things you'd expect: hellfire and brimstone, accusatory pointing at his flock. She always looked bored. When we stood up to sing, she only mouthed the words.

I think I got my skepticism from her.

When Colonel Kolansky and the others came to recruit me, when I was in the middle of my postdoc, it was easy for me to accept the position. I didn't have any family to speak of; no girlfriend, no particularly close friends save my colleagues, all of whom did have families—spouses and children. My father had disowned me when I went away to college, when I didn't enter the seminary the way he had, and his father, and his father's father. I wrote letters to my mother until the day she had her accident. She wrote back, told me she was proud of me, proud I'd found my own way.

I went to her funeral and my father didn't look me in the eye. I didn't go to my father's funeral, four months later, because by then I had already moved out to the base, I'd already left my old life behind entirely.

When you asked about my family that night in the bar, I immediately thought of my mother, washing dishes at the sink, her hair spun gold from the setting sun. I still missed her profoundly. Maybe that was the real reason I changed the subject: the sudden ache in my chest, the sudden swell of sorrow. In those days, I sometimes wondered if maybe it was worth it to believe in Heaven, if such a belief, juvenile though it might be, could subdue the dolor of loss.

Lately, with all that's happened, I've begun to ask myself that question again.

I picture you. Not you as you were back then, drinking in the bar, dancing in the blue lights of the stage, but as you are now. As I imagine you are now. You dye the grey out of your dark hair. You wear blue jeans with pearls and high-heeled shoes and lipstick instead of sequined mini-dresses and too much eyeliner. Although really, I have no idea what you look like. I've cobbled this all together from pictures of the day workers' wives.

I like to imagine that you live in the desert, even though I know how unlikely that is. You even told me once—"I'll never live in the desert again. It turns you into sand, living out there." But I picture you in the desert because in the desert it's safer. I know how ridiculous it is, me wanting you to be safe. You probably don't even remember my name. You probably don't even remember what I look like.

But we were friends, many years ago, even if you've forgotten me. You were one of my only friends. I told you that once and you smiled and said, "Yeah, we're friends," and then we went walking outside in the shower of neon lights, side by side, our hands not touching. We rarely touched. It's been so long, I've forgotten those moments: probably all accidental, our shoulders brushing against each other when we came to a doorway, your foot knocking against my leg underneath the table, brusquely. I still thought of sex back then, before I let work subsume my desires, so I'm sure I clung to the instances of our accidental touching for days afterward.

I did enjoy our walks, though. Maybe it was good our relationship was so chaste. It's not like it could have gone anywhere, otherwise.

Besides, you seemed to know all the secret places in Vegas, so I didn't really want anything more: all the shabby little casinos where the dealers looked at us askance and they served import beer on tap, all the desert-dusty bars where singers strummed guitars and looked dolefully out at the audience. You took me away from the Strip, out to the trailer-strewn suburbs, where the city gives way to the desert. We went to a party at one of those trailers, I remember, jewel-colored lights stretching from the roof to the chain-link fence. The music, all soul and R&B from the '50s, echoed out into the empty empty night and it almost seemed like they might hear it at the base, even though I knew of course that wasn't possible. I remember dancing with you in the trailer's dusty yard, dry sand kicking up around our ankles, your hair falling flat and damp from the sweat and the heat.

That was the night you got drunk and we dragged plastic lawn chairs out away from the party and looked up at the milky swirl of stars. You smoked one cigarette after another and told me how you'd grown up in the middle of the desert, maybe three hours or so north of Vegas. How your mom waited tables at a diner in Eureka, how you used to find the entrances to old mines with your brothers and the three of you would drop down one by one into that unfathomable dark, looking for gold or snakes or ghosts. You spent your entire childhood covered in dust, you told me, and now you'll spend your entire adulthood covered in glitter.

"The only thing I liked about the desert," you said, leaning back in your chair, running your fingers around the edge of your beer can, "was the wind chimes. You know? You can hear 'em everywhere. They hang them up for protection and good fortune. My mom had three." Your voice was already beginning to slur, and when I glanced over at you I saw you slump down in your chair. You frowned. "Good fortune, my ass," you said.

I've always remembered that conversation. Whenever we went out with the convoys to watch the launch tests, I sometimes heard the tinkling of wind chimes, very faint, and in that moment those wind chimes were a connection between you and me, something I'd thought impossible. There weren't supposed to be any people around for miles where we tested but we came across them occasionally, living out of trailers, wind chimes breaking the air into tiny fragments of glass. No one else ever talked about it, not the soldiers, not the other researchers, and I sometimes wondered if they ever paid attention to anything else at all.

We stayed out all night. You passed out in your chair, and I stared up at the sky until I fell asleep. Later, the heat of the mid-morning summer sun woke me up, the skin of my nose already starting to burn. And when I glanced over in your direction you were still there, snoring faintly, your skin pink, and it made me happy to wake up next to you.

One thing we did have in common, aside from the wind chimes, was that neither of us spoke of our jobs at all, and so I saw you dance only once. I always got the impression you didn't want me to watch you, because I knew you as Rachel and when you danced you had another name—Nevada Starr, Starry Night, something along those lines. It doesn't matter. You never actually told me. Besides, I always felt that you liked me on an intellectual level, which I was used to, and had more or less come to expect, after college.

I learned your stage name that night when I slunk down to the theater when you said you were working. I sat at one of the back tables so you wouldn't see me. You came out on stage wearing a burgundy dress, a burgundy wig. When you shimmied out of the dress you winked out into the darkness, right at me. I swear it. I almost bolted from the room, convinced you knew I was there. But then the lights caught on the strands of pearls that fell in swoops along the lines of your body, concentrating in two circles on your torso and a single narrow triangle at your legs. You twisted your spine contrapposto, and I saw the muscles of your back moving beneath your skin. The pearls began to drop away. It'd been so long since I'd seen the naked form of a woman I knew.

At the very end, you gyrated in the halo of the spotlight, and you whipped your wig off into the crowd, your hair tumbling down around your shoulders. Seeing your real hair, then, on that stage, felt peculiarly voyeuristic, as if it were a mistake, something the audience wasn't meant to see. There was only a second of it—the stage lights shut off immediately. But even in that sudden darkness I still saw the outline of you, like an afterimage, running towards the wings, your real hair fluttering out behind you like the contrail of a jet plane.

So yes, I thought of you sexually then, because I was a young man and I lived underground and served my country in ways I can't ever confess to, under the threat of fines and imprisonment, and you talked to me one night in a bar in a city built entirely out of neon and luck. A city of no substance. The best thing about Las Vegas was always you.

After we found out the invasion was coming, I convinced one of the soldiers to drive me to the little town forty minutes or so outside of the base. I had to get away. You know the kind of fear that grips you in the pit of your stomach, that turns you cold and clammy with dread? That's how it was. It's only lessened slightly since then. And the entire base was heavy with that fear, even though only maybe ten of us knew about the signal, knew what it meant.

In town I bought the soldier a pack of cigarettes and a six-pack of beer at the little gift shop they built along the highway for UFO watchers. He went outside and leaned against the window and chain-smoked while I wondered up and down the aisles, looking at the rows of miniature ceramic aliens, green-skinned and big-eyed. Aliens on T-shirts. On coffee mugs and key chains. It always annoyed me how the entire world seemed to know what we were up to and I still wasn't allowed to say anything.

The store had maybe five or six wind chimes hanging from an old coat rack. They were small and sounded tinny and high pitched when I flicked them with my thumb. I bought one. The metal tubes were painted pale green and an aluminum butterfly perched atop the hook. I carried it outside and the soldier squinted at me in the white sunlight, his cigarette drooping from his mouth.

"I've never understood you eggheads," he said. He reached down and picked his six-pack up off the cement. "Thanks for the smokes, though."

When we got to the base I hung the wind chime on a nail on the back side of one of the hangars, where no one would see it. And even though it was stupid and deep down I knew better, I still hoped the sound of it would bring us all protection and good fortune.

I sometimes wonder where you were when the invasion happened. I always imagined that you left the country like you always said you wanted to, that you're living in some flat in Paris or Naples, the former trophy wife of a millionaire. When the ships began to appear overhead I'm sure you ran out onto your balcony—maybe you were still in your underwear, a robe tossed loosely around your shoulders—and you stood with your fingers gripping the metal banister until your knuckles turned white, the sky falling in flakes of ash all around you. Even I went out and looked at the ships. I knew they were coming, I'd known for weeks, but I still climbed up on the roof of the base with all the day workers and the soldiers and the other researchers and we watched the faint outline of the ship shimmering above the horizon. The air was thick with that ashy burned-out smell, the smell that's everywhere these days. It reminds me of cigarettes in the bar of the Tropicana.

Is it strange or is it sad or is it both that in the moment I saw those ships approaching our planet, my first thoughts were of you?

I have this fantasy where I save the world in secret. I don't think of it often—only in the calm seconds between work and panic, when I let myself stop in the middle of the lab so that I don't collapse in a heap on the floor. It's my driving goal, to figure out the way to save the world, to take it back. I tell myself I'm sure that I can do it, that we can all do it, all of us working together underground.

And I think of you, wherever you are, whoever you've become, and I hope that when I save the world I save you with it. Even though you'll never know it was me.