"Open the gate!" the steward hollers.

And that's it.

Alina and I are through the second steel gate and making our way along a glass tunnel. Other tourists saunter alongside us. We lean against the curved glass to wait for Bea.

"Do you have oxygen?" I ask Alina. Shaking a little, she pulls an airtank from her backpack, then attaches the cylinder to her hip using the belt. Once she pulls the transparent silicone mask over her mouth and nose, she tightens the straps at the back to ensure it is airtight. I take out my own tank and do the same.

When Bea gets through, she runs to us, though she shouldn't, and before I get a chance to speak, she throws herself at me. She presses into me so tightly it pinches. "Don't break my ribs!" I say. I know she was worried. I don't want to dwell on it. "I'll help you with your mask," I say. "We have to get going."

We walk down the sun-drenched glass tunnel-Bea, Alina, and me. We push open the revolving doors at the end. And we step, as one, into the airless planet.

PART II.

THE OUTLANDS.

10.

BEA.

Without speaking or even looking at each other, we've somehow agreed to stick with Alina for a while longer; it would seem too strange if she wandered off alone. And we've also decided to get as far away from the pod and day tourists as we can. Most of the other tourists are as silent as we are-focused on breathing, avoiding panic as they move farther and farther from guaranteed air.

We could talk if we wanted to-it's easy to be heard through the holes in our blowoff valves; it's just that we aren't used to having our faces covered. The masks keep us alive, but mine is also keeping my nose warm. I gave Alina my scarf. What else could I do? Watch her shivering and ignore it? Quinn gave her a spare sweater and tried to give her his green gloves, too, but she refused. They finally agreed to one glove each. And so now they look a little like two parts of the same person.

I had hoped that once rigged out in her mask, Alina wouldn't look so pretty, but her round eyes and sharp eyebrows stand out even more. And she was smart enough to fit the straps under her hair so that it falls down over them at the sides. I stupidly pulled mine tight over my black bob, so my head must be the shape of a mushroom.

The only other time I visited The Outlands was for a school trip when I was around seven. We were all being offered a chance to try breathing without a mask, taking turns as the teacher slowly drew it from our faces and cheerfully told us to inhale. It was like drinking fire. The teacher watched as I gasped. She smiled, nodded, kept the facemask away from my nose and mouth, and then, when I began to stagger, she snapped the mask back into place and tightened the straps. "Wasn't that an experience?" was all she said. I always wondered what the purpose of that trip was. Were we being taught how desperately we needed the pod? It was certainly a way to ensure I never tried to defect. So I have to wonder what is happening to Alina to make her flee like this.

Behind us, the sunrise is pink. The light hits the pod in such a way that it could be a beautiful glimmering mountain if it weren't for the four recycling stations steaming next to it. There is nothing else close to the pod. All debris was cleared a long time ago. It's only now that we are at a distance that we come upon the rubble of the world as it was before The Switch. There are rows of tumbledown houses along cracked, warped roads, and everywhere the remains of old vehicles covered in what looks like ivy. Even though it's winter and the frost is probably freezing the roots off everything, the earth is not as barren as I imagined. Besides the ivy, tufts of wild grasses and moss eat away at the ruins. I carefully sidestep anything living, anything growing, though now and again I bend down to brush the greenery with my hand.

What I love most is the dirt. Everything is so clean in the pod. Even the streets in Zone Three are spotless. In the short time we've been walking, my boots are scuffed and brown. The old roads are often impassable. The paths we are using are muddy, worn tracks made by the tourists, spreading out erratically from the pod like veins. I take off my gloves and reach down to dig up a handful of cold, hard, pebbled soil. I rub it between my fingers so that it crumbles, until I'm left with only one small blue stone. I pinch it between my thumb and forefinger. Alina is by my side, between Quinn and me, and she is watching. Her eyes squint so I know she's smiling. But I don't know what her smile means-maybe she is laughing at me. I throw the blue stone back onto the ground and brush my hands against my pants. And I notice Alina's laces are undone. I consider not mentioning it. But I don't. I point down at her feet. She nods and bends to tie her shoelaces. When she stands up again I smile at her, too. I think I might be trying to prove how nice I am, so she'll be on my side. If I'm kind to her, maybe she won't take Quinn away from me.

Within half an hour, we pass The Cenotaph. A crowd has already gathered to weep and read the names of their dead loved ones from a mammoth pentagonal stone. The actual burial places are many miles from the pod to prevent the spread of disease, too far for people to travel to. So the Ministry erected this monument to give the grief-stricken a place to remember. Not that many auxiliaries can afford the air to get here. When my grandmother died, we had to hold a small vigil at home instead. "Are there names of people you know engraved on The Cenotaph?" Quinn asks Alina.

She turns to him and her eyelids flutter closed for a moment. "No," she says. "My parents' names aren't on it."

He opens his mouth to respond, but I pinch him. It isn't his business. Whatever it is. Then he says, "Can you imagine how big that thing would have to be if they made a monument to everyone lost in The Switch?" We all look at The Cenotaph but quickly turn away. The truth is, it's impossible to imagine how far it would have to stretch.

Eventually the hundreds of armed stewards who guard the pod in concentric circles thin out, and after another hour of walking, there is no one ahead of us and only a scattering of ambling day-trippers almost a mile behind-shifting dots in the distance.

We cut through an old school yard, past rotting wooden benches and a capsized basketball hoop. At the edge of the yard, garbage cans lie on their sides, bottles spilling out of them, the plastic ones intact. We reach a wide road, climb a set of stairs, and cross a concrete bridge to the other side. When we get there, Alina stops and stands with her hands on her hips. "This is as far as we go together," she says. I look at Quinn.

"You won't be safe on your own," he says.

"I've enough air to get me to where I'm going." She knocks on her tank with her knuckles and gives us the thumbs-up. "I don't need as much as you. I've already tightened my valve."

"Where exactly are you going?" Quinn wants to know.

"West," she tells him.

"You'll die before you even make it to the city, you know."

"I'm going to a safe place."

"You have to tell us what's going on. Do you know what kind of hassle I'm going to get when my father hears I helped the RATS?"

"We prefer to call ourselves the Resistance," Alina says.

Quinn's neck blushes. "I mean, I know you can't be as bad as they say. It's just that ... well, my father will ground me for a month. Two months, maybe. But if you explain what this is about, he might be able to help." Alina grimaces. If Quinn is trying to impress her, he's doing a terrible job; she's being tracked by the Ministry, but he's in trouble with his dad-the two don't quite hold the same weight. And the chances of Quinn's father being on her side are slim.

"Quinn-" I begin, but he waves me away.

"Thank you for helping me. But you can't come any farther. It isn't safe." Alina looks at me. Why? Do I seem weak? Surely she's as weak as I am, if she's an auxiliary, too.

"You know, you haven't even asked us our names," Quinn says. "It would be nice to think you want to know our names." He sounds hurt.

"You're Quinn Caffrey. I found that out at the border."

"This is Bea," he says, and places a hand on my shoulder.

"Nice to meet you," she says formally. She shakes our hands and turns to leave. "Thank you again for the clothes. I would have frozen." She stares at the eddying clouds and clusters of derelict buildings on the horizon. The landscape changes quickly-one minute it's a huge expense of wasteland, ground that was once used for mass farming, the next it's tight knots of rubble.

As she starts to walk away, Quinn calls after her. "You don't trust us." He looks at me for support. I shrug. Why should she trust us? I don't trust her. I don't even know her.

Alina stops and turns. "This is a decent place to camp," she says, ignoring Quinn and gesturing to the land surrounding us. "If you go any farther it's sort of depressing and quite dangerous, unless you brought hard hats." She tries a smile. "A little north of here was a forest once. The whole area. Monk Wood." I roll my eyes to show her that she needn't think we're stupid; we know about Monk Wood. Everyone knows. And that was exactly where we planned to camp all along, though we didn't plan on getting to it so quickly. We were going to wind our way through some of the old villages rather than cutting right across the country. The route Alina chose bypassed most traces of the old civilizations.

"Fine," Quinn says, defeated.

"Good luck," I mumble, and then, "Have you any food?" because even though I don't want Alina sticking around, I don't want her to starve. She shakes her head. I reach into my backpack and pull out a box of crackers. When I hand them to her she smiles, and with her empty hand she waves, though she is no more than three paces from us.

Quinn and I watch her hike toward the rows of crumbling houses in the distance. She seems to know exactly where she's going.

The sun has fully risen and is now high in the murky sky. When I look around, I can't see any other people at all-not even moving dots. Quinn and I are completely alone. We sit on an unsteady stone wall and eat a couple of coco protein bars. Eating isn't easy: with one hand we pull the lower half of our masks away from our faces and awkwardly slip pieces of food into our mouths, and with the other hand we make sure our noses stay completely covered.

Quinn has been brooding ever since Alina dissolved into the horizon. For a while I ignore his scowl, hoping he'll come around, but he's probably going to be in a grump our entire trip unless I let him talk about it.

"She must have broken the law," I say. I can't bring myself to use her name.

"Whatever she did, she's in big trouble. I hope we helped her."

"Come on, Quinn, she didn't seem lost. She knows exactly what she's doing. Anyway, what do you want to do? Stalk her?" Quinn continues to stare at the derelict buildings in the distance. Suddenly he stops chewing, lightly slaps himself across the side of the head, and stares at me. I stare back. He puckers his lips and bumps his facemask against mine, making a loud kissing sound with his lips. I feel my face getting warm and fiddle with the zipper on my jacket so he won't notice.

"What is it?" I say, pulling at the hair pinched by the straps of my facemask. It feels constrictive and uncomfortable; I adjust the rubber strap at the back of my head.

"You're right, we have to follow her. If we don't, she's all alone. She could die. There are drifters, and look at that sky-the weather is only going to get worse, and she isn't ready for it. You know what we'll be, if anything happens to her? Killers, that's what."

"How will we be killers? When she needed our help, she asked for it. She doesn't want our help anymore because she's got people out here, Quinn. People way tougher than us, I'm guessing. We aren't her friends. She told us to get lost." As I say it, Quinn bites the insides of his mouth, hurt.

"Don't you want adventure, Bea? Here it is. A real adventure. Not some game we've invented like when we were little kids. Don't you feel alive?"

"I actually feel very alive. But if we try tracking that girl, I might not feel alive for long. This oxygen won't last forever." I rap my fingers against the tank.

"We have plenty of air. We brought enough for two full days. And anyway, she as good as told us that where she's going, there'll be plenty of the stuff. So we'll get a refuel."

"Oh, Quinn." I want to cry. I want to tell him that none of this is fair; we'd planned a trip together, the two of us, and I hoped he'd discover me out here, not another girl. But if I refuse I'll only have one choice, and that will be to trudge back to the pod on my own. And then what will he think of me?

"I know you're afraid," he says. This makes me feel a little better. At least he's thinking about my feelings. "We need weapons. Did you bring a weapon?" He jumps down from the wall.

"Why would I bring a weapon?" I ask.

"I have a knife I was planning to use for preparing food and stuff." He pulls out a knife with a long, thick blade and passes it to me. The hilt of the knife is heavy and the blade is sharp. "You keep that," he says, and hands me its sheath. "I have rope, too. Oh, and I have a hammer for the tent pegs."

"Exactly how mad do you think she'll be that we followed her?" I tease.

"The weapons are for the drifters," he says without smiling, and bends down to tighten the laces on his boots. Then he tightens my laces, too. "Ready?" he asks, standing up.

"Drifters?" We've all heard stories about the drifters, old pod prisoners and lunatics who managed to escape and set up rudimentary air systems to keep themselves alive. They lie in wait to terrorize tourists who venture too far from the pod. They live in the gray nooks and crannies of the city. But how can this be true? Even if the drifters managed to escape and found a way to breathe, they'd certainly starve to death. It has to be a rumor-a legend. "I'd be too scared to use this," I admit, and hand back the knife, which Quinn slips through a loop in the band of his pants.

"Wanna get going?" he asks. He starts to pack away lunch, puts on his one green glove, and wipes his forehead with it. "If we wait much longer she'll be too far ahead and we'll never find her." So that's it. I'm going to follow Quinn, who's following Alina, and we are all going to march willingly into the pit of this forgotten city.

11.

ALINA.

I didn't want to take the old tarmacked roads and be visible from a distance. I would prefer to forge my own route into the city. But it would be hard to find a way through without having to climb dozens of dicey walls and fences. And it's started to rain. Hardly a downpour, but enough to make mud of the fields. I pull the scarf Bea gave me over my head and tie a knot to keep it in place. And so I walk along the deserted, warped road instead of taking a rougher, safer track.

Tourists can walk for miles without being reminded of the carnage out here, and in the pod we all try to forget what The Outlands really look like. The farther from the pod I get, the worse the devastation. There is rubble and garbage everywhere-evidence of the chaos at the end: hundreds of rusted-out cars and buses and vans and shopping carts and blanched tree stumps and collapsed telephone poles. Every now and again I spot something simple and ordinary-like toothbrush. What happened to its owner? The old billboards remain in place but their messages have long since faded away. It is eerily quiet. My own footsteps are the only sounds I can hear. I can no longer make out the hum of the pod's recycling stations. There are no trams rattling along. And there are no people, of course. No one to reclaim all the spoons, trays, sunglasses, kites, wheelbarrows, bowls, and everything else.

There were people. Many years ago. There were millions across this country until The Switch, when the population dwindled to half a percent of what it had been, not merely here, but everywhere. Across the whole planet, the bulk of humanity was annihilated within a few years. I shudder to think of all the bodies that must be buried in the yards around me. Because that's what people had to resort to, eventually, when the graveyards started to overflow. Then even the mass graves couldn't take the numbers, so they stopped burying the people. They burned them instead. And when the only ones left were weak and choking, they stopped doing even that; they simply left the bodies to rot wherever they fell.

I recall the video footage from history class of decaying bodies in beds and baths. Bodies on the roads next to abandoned cars or in them. People were still sitting up-bodies large and small, adults and babies, some bodies with the flesh decomposing, some already stripped leaving nothing but an arrangement of bones. The animals had gone long before that, destroyed in droves as soon as people figured out what was happening. Used for food when the farmers quit farming. Even the domestic animals were eaten up. No one entertained the idea that the creatures might have had just as much right to the air as the people. Then again, no one thought the trees of much value either.

In the distance, thunder rumbles, and it starts to rain. As I gaze upward I imagine that a crooked telephone pole is really a branchless, leafless tree. The thought makes me angry. I know why they cut the trees down. I know the problem: the world's population was soaring and people needed to eat. And the solution was to log all remaining forests and use the land for farming. But how could everyone have been so stupid as to imagine that the oceans alone could provide the planet with the oxygen it needed to survive? And they didn't care what they used to grow food. The trees, the soil-nothing was safe. No one predicted the havoc billions of gallons of toxic runoff from agriculture would cause the oceans. No one imagined the oceans could die. And not so quickly. But that's how things usually go. We always think we have time. We didn't. Within years the oxygen level in the atmosphere plummeted to four percent.

This isn't the version we get at school. There we're told it was China's fault-all those factories. It was India's fault-all those babies. It was America's fault-all those shoppers. The rain begins to come down harder. I open my mouth to the sky.

I'm meant to think of myself as one of the lucky ones-a descendent of someone who managed to survive. And how did humanity survive? We have Breathe to thank for that. I look over my shoulder, but the pod is well and truly out of sight. Breathe managed to concoct a solution, working away in their laboratories using scuba-diving airtanks to keep themselves alive. The tanks were filled and handed out to the deserving in society first-the doctors, judges, politicians. The artists didn't stand a chance-what use could they be? And the homeless? The sick? They were the first ones to rot.

But the government ran a lottery, too; half the tanks and pod passports were given to randomly selected citizens under thirty years old. And so my grandparents, who were young and fit, both won places and were given tanks while they waited for the pod to be built.

My grandparents didn't know each other at that time. They met in the pod, when they worked together in one of the recycling stations. They both died when I was small, but they never could believe they'd spent most of their lives under a glass dome. The pod was meant to be a short-term solution while the trees and plankton replenished themselves. But that was just a fairy tale: anyone with half an ounce of sense knew they'd never again live in the outside world or taste organic air. The planet needs a lot more time to heal itself. More years than we can imagine. Even now, so many years after The Switch, the oxygen level in the atmosphere is only up to six percent.

The Ministry works hard to ensure that its citizens hold out no hope of ever living beyond the pod, but maybe it was worse for my grandparents because they knew what they were missing. And they'd witnessed The Switch firsthand. They never got over it.

All four of my grandparents have their names engraved on The Cenotaph, but there was no point in telling Bea and Quinn that or stopping to look. I have no interest in seeing lists of the dead.

I pass dilapidated buildings, most of which are old houses, crumbling now and enveloped in moss. Many of them are piles of rubble. The silence is beautiful.

I notice a stack of bones on the pavement. A whole skeleton perfectly decayed-white and dry-pulled together into a neat pile, the skull balancing on top. Who did this? And when? Could these bones belong to Abel? No sooner do I think this than I realize it's a ludicrous idea. How would he have made it all the way out here? Plus he's been dead no longer than a couple of days. There's no way he could be all bones yet. Is there? Which stage of decay is he in? Is he oozing and bloated? Is he filling with maggots?

I try to picture Abel as I last saw him: waving good-bye from the entrance to my building; giving me a theatrical wink when I tightened the straps on my backpack containing the tree clippings; congratulating me. He had no idea he was as good as dead.

And I might be dead if I'd stayed in the pod. If I'd been held at the border. If Quinn and Bea hadn't saved me. Quinn looked so hurt when I left them. He'll probably head back home and tell his father all about it. I'm sure he wants to be a good guy, but at the end of the day he's Premium, and Premiums are not to be trusted. They have too much to lose. And I couldn't bring Bea along; people in love are the most dangerous of all, the most likely to do something rash. I proved that. I wanted to love Abel. Now that he's dead I almost feel that I did love him even though nothing happened between us. Since when does someone being dead make you feel more affection for him?

I'm doing it again, thinking about Abel when I should be focused. I could be ambushed at any time if I don't watch out. The place appears to be deserted, but that doesn't mean it is. There could be drifters anywhere. And Breathe could be out here, too.

Suddenly there is a rumble, like an old wheel lumbering toward me. I spin around and drop to the ground. I see nothing suspicious. The road is clear. Then the rumble sounds again and I see it's coming from a lamppost that has fallen against a building. The wind is rolling the lamppost back and forth on a window ledge, creating the deep echo.

The last time I was out of the pod Silas was with me. He had a gun, and I had a knife. No one came near us. We didn't see one drifter. Why couldn't I have remembered to bring a weapon? I need to protect myself. But with what? I scan the street. There's nothing I could use except rocks and broken bricks. But if someone gets too close to me, rocks will be useless. I need something to swing.

Though most of the street is lined with piles of rubble, some of the houses are still standing. And if I'm lucky, there will be kitchens in these houses, and knives in the kitchens, whole drawers filled with blades and skewers. And I'm cold, despite the one green glove and sweater Quinn gave me. The rain has turned to sleet now and the scarf around my head is completely sodden. I've nothing waterproof with me at all.

The nearest houses have had their doors kicked in and windows broken, which means they've probably been pillaged already. I pass a gas station with several cars rusting in the lot. One car even has the gas pump sticking out of its tank. On the other side of the road is a small hospital. I could definitely try in there. But I'm scared of what I'd find-how many stacks of old bones, how many beds of bodies. Up ahead are more houses, big ones with heavy wooden doors, and not all of them look like they've been ransacked. Apart from the moss covering them, they could very well be inhabited. That's not possible though; I banish the thought because it's actually scarier than imagining the houses empty.

My teeth are chattering. I decide to take shelter in one of the grander-looking houses.

I climb a low stone wall and make my way through a front garden, trying not to slip on the slick, mossy stones.