Trees, overgrown and huge, grow beyond the cement fixtures intended to keep them enclosed, their roots sprawling over the pavement. Perched on the edge of one rooftop is a row of black birds like the ones tattooed on Tris’s collarbone. As the truck passes, they squawk and scatter into the air.

This is a wild world.

Just like that, it is too much for me to bear, and I have to back up and sit on one of the benches. I cradle my head in my hands, keeping my eyes shut so I can’t take in any new information. I feel Tris’s strong arm across my back, pulling me sideways into her narrow frame. My hands are numb.

“Just focus on what’s right here, right now,” Cara says from across the truck. “Like how the truck is moving. It’ll help.”

I try it. I think about how hard the bench is beneath me and how the truck always vibrates, even on flat ground, buzzing in my bones. I detect its tiny movements left and right, forward and back, and absorb each bounce as it rolls over the rails. I focus until everything goes dark around us, and I don’t feel the passage of time or the panic of discovery, I feel only our movement over the earth.

“You should probably look around now,” Tris says, and she sounds weak.

Christina and Uriah stand where I stood, peering around the edge of the canvas wall. I look over their shoulders to see what we’re driving toward. There is a tall fence stretching wide across the landscape, which looks empty compared to the densely packed buildings I saw before I sat down. The fence has vertical black bars with pointed ends that bend outward, as if to skewer anyone who might try to climb over it.

A few feet past it is another fence, this one chain-link, like the one around the city, with barbed wire looped over the top. I hear a loud buzz coming from the second fence, an electric charge. People walk the space between them, carrying guns that look a little like our paintball guns, but far more lethal, powerful pieces of machinery.

A sign on the first fence reads BUREAU OF GENETIC WELFARE.

I hear Amar’s voice, speaking to the armed guards, but I don’t know what he’s saying. A gate in the first fence opens to admit us, and then a gate in the second. Beyond the two fences is . . . order.

As far as I can see, there are low buildings separated by trimmed grass and fledgling trees. The roads that connect them are well maintained and well marked, with arrows pointing to various destinations: GREENHOUSES, straight ahead; SECURITY OUTPOST, left; OFFICERS’ RESIDENCES, right; COMPOUND MAIN, straight ahead.

I get up and lean around the truck to see the compound, half my body hanging over the road. The Bureau of Genetic Welfare isn’t tall, but it’s still huge, wider than I can see, a mammoth of glass and steel and concrete. Behind the compound are a few tall towers with bulges at the top—I don’t know why, but I think of the control room when I see them, and wonder if that’s what they are.

Aside from the guards between the fences, there are few people outside. Those who are stop to watch us, but we drive away so quickly I don’t see their expressions.

The truck stops before a set of double doors, and Peter is the first to jump down. The rest of us spill out on the pavement behind him, and we are shoulder to shoulder, standing so close I can hear how fast everyone is breathing. In the city we were divided by faction, by age, by history, but here all those divisions fall away. We are all we have.

“Here we go,” mutters Tris, as Zoe and Amar approach.

Here we go, I say to myself.

“Welcome to the compound,” says Zoe. “This building used to be O’Hare Airport, one of the busiest airports in the country. Now it’s the headquarters of the Bureau of Genetic Welfare—or just the Bureau, as we call it around here. It’s an agency of the United States government.”

I feel my face going slack. I know all the words she’s saying—except I’m not sure what an “airport” or “united states” is—but they don’t make sense to me all together. I’m not the only one who looks confused—Peter raises both eyebrows as if asking a question.

“Sorry,” she says. “I keep forgetting how little you all know.”

“I believe it’s your fault if we don’t know anything, not ours,” Peter points out.

“I should rephrase.” Zoe smiles gently. “I keep forgetting how little information we provided you with. An airport is a hub for air travel, and—”

“Air travel?” says Christina, incredulous.

“One of the technological developments that wasn’t necessary for us to know about when we were inside the city was air travel,” says Amar. “It’s safe, fast, and amazing.”

“Wow,” says Tris.

She looks excited. I, however, think of speeding through the air, high above the compound, and feel like I might throw up.

“Anyway. When the experiments were first developed, the airport was converted into this compound so that we could monitor the experiments from a distance,” Zoe says. “I’m going to walk you to the control room to meet David, the leader of the Bureau. You will see a lot of things you don’t understand, but it may be best to get some preliminary explanations before you start asking me about them. So take note of the things you want to learn more about, and feel free to ask me or Amar later.”

She starts toward the entrance, and the doors part for her, pulled open by two armed guards who smile in greeting as she passes them. The contrast between the friendly greeting and the weapons propped against their shoulders is almost humorous. The guns are huge, and I wonder how they feel to shoot, if you can feel the deadly power in them just by curling your finger around the trigger.

Cool air rushes over my face as I walk into the compound. Windows arch high above my head, letting in pale light, but that is the most appealing part about the place—the tile floor is dull with dirt and age, and the walls are gray and blank. Ahead of us is a sea of people and machinery, with a sign over it that says SECURITY CHECKPOINT. I don’t understand why they need so much security if they’re already protected by two layers of fence, one of which is electrified, and a few layers of guards, but this is not my world to question.

No, this is not my world at all.

Tris touches my shoulder and points down the long entryway. “Look at that.”

Standing at the far end of the room, outside the security checkpoint, is a huge block of stone with a glass apparatus suspended above it. It’s a clear example of the things we will see here that we don’t understand. I also don’t understand the hunger in Tris’s eyes, devouring everything around us as if it alone can sustain her. Sometimes I feel like we are the same, but sometimes, like right now, I feel the separation between our personalities like I’ve just run into a wall.

Christina says something to Tris, and they both grin. Everything I hear is muffled and distorted.

“Are you all right?” Cara asks me.

“Yeah,” I say automatically.

“You know, it would be perfectly logical for you to be panicking right now,” she says. “No need to continually insist upon your unshakable masculinity.”

“My . . . what?”

She smiles, and I realize that she was joking.

All the people at the security checkpoint step aside, forming a tunnel for us to walk through. Ahead of us, Zoe announces, “Weapons are not allowed inside this facility, but if you leave them at the security checkpoint you can pick them up as you exit, if you choose to do so. After you drop them off, we’ll go through the scanners and be on our way.”

“That woman is irritating,” Cara says.

“What?” I say. “Why?”

“She can’t separate herself from her own knowledge,” she says as she draws her weapon. “She keeps saying things like they’re obvious when they are not, in fact, obvious.”

“You’re right,” I say without conviction. “That is irritating.”

Ahead of me, I see Zoe putting her gun into a gray container and then walking into a scanner—it is a man-sized box with a tunnel through the middle, just wide enough for a body. I draw my own gun, which is heavy with unused bullets, and put it in the container the security guard holds out to me, where all the others’ guns are.

I watch Zoe go through the scanner, then Amar, Peter, Caleb, Cara, and Christina. As I stand at the edge of it, at the walls that will squeeze my body between them, I feel the beginnings of panic again, the numb hands and the tight chest. The scanner reminds me of the wooden box that traps me in my fear landscape, squeezing my bones together.

I cannot, will not panic here.

I force my feet to move into the scanner, and stand in the middle, where all the others stood. I hear something moving in the walls on either side of me, and then there’s a high-pitched beep. I shudder, and all I can see is the guard’s hand, motioning me forward.

It is now okay to escape.

I stumble out of the scanner, and the air opens up around me. Cara gives me a pointed look, but doesn’t say anything.

When Tris takes my hand after going through the scanner herself, I barely feel it. I remember going through my fear landscape with her, our bodies pressed together in the wooden box that enclosed us, my palm against her chest, feeling her heartbeat. It’s enough to ground me in reality again.

Once Uriah is through, Zoe waves us forward again.

Beyond the security checkpoint, the facility is not as dingy as it was before. The floors are still tile, but they are polished to perfection, and there are windows everywhere. Down one long hallway I see rows of lab tables and computers, and it reminds me of Erudite headquarters, but it’s brighter here, and nothing seems to be hidden.

Zoe leads us down a darker passageway on the right. As we walk past people, they stop to watch, and I feel their eyes on me like little beams of heat, making me warm from throat to cheeks.

We walk for a long time, deeper into the compound, and then Zoe stops, facing us.

Behind her is a large circle of blank screens, like moths circling a flame. People within the circle sit at low desks, typing furiously on still more screens, these ones facing out instead of in. It’s a control room, but it’s out in the open, and I’m not sure what they’re observing here, since all the screens are dark. Clustered around the screens that face in are chairs and benches and tables, like people gather here to watch at their leisure.

A few feet in front of the control room is an older man wearing a smile and a dark blue uniform, just like all the others. When he sees us approaching, he spreads his hands as if to welcome us. David, I assume.

“This,” the man says, “is what we’ve waited for since the very beginning.”

CHAPTER FIFTEEN

TRIS

I TAKE THE photograph from my pocket. The man in front of me—David—is in it, next to my mother, his face a little smoother, his middle a little trimmer.

I cover my mother’s face with my fingertip. All the hope growing inside me has withered. If my mother, or my father, or my friends were still alive, they would have been waiting by the doors for our arrival. I should have known better than to think what happened with Amar—whatever it was—could happen again.

“My name is David. As Zoe probably told you already, I am the leader of the Bureau of Genetic Welfare. I’m going to do my best to explain things,” David says. “The first thing you should know is that the information Edith Prior gave you is only partly true.”

At the name “Prior” his eyes settle on me. My body shakes with anticipation—ever since I saw that video I’ve been desperate for answers, and I’m about to get them.

“She provided only as much information as you needed to meet the goals of our experiments,” says David. “And in many cases, that meant oversimplifying, omitting, and even outright falsehood. Now that you are here, there is no need for any of those things.”

“You all keep talking about ‘experiments,’” Tobias says. “What experiments?”

“Yes, well, I was getting to that.” David looks at Amar. “Where did they start when they explained it to you?”

“Doesn’t matter where you start. You can’t make it easier to take,” Amar says, picking at his cuticles.

David considers this for a moment, then clears his throat.

“A long time ago, the United States government—”

“The united what?” Uriah asks.

“It’s a country,” says Amar. “A large one. It has specific borders and its own governing body, and we’re in the middle of it right now. We can talk about it later. Go ahead, sir.”

David presses his thumb into his palm and massages his hand, clearly disconcerted by all the interruptions.

He begins again:

“A few centuries ago, the government of this country became interested in enforcing certain desirable behaviors in its citizens. There had been studies that indicated that violent tendencies could be partially traced to a person’s genes—a gene called ‘the murder gene’ was the first of these, but there were quite a few more, genetic predispositions toward cowardice, dishonesty, low intelligence—all the qualities, in other words, that ultimately contribute to a broken society.”

We were taught that the factions were formed to solve a problem, the problem of our flawed natures. Apparently the people David is describing, whoever they were, believed in that problem too.

I know so little about genetics—just what I can see passed down from parent to child, in my face and in friends’ faces. I can’t imagine isolating a gene for murder, or cowardice, or dishonesty. Those things seem too nebulous to have a concrete location in a person’s body. But I’m not a scientist.

“Obviously there are quite a few factors that determine personality, including a person’s upbringing and experiences,” David continues, “but despite the peace and prosperity that had reigned in this country for nearly a century, it seemed advantageous to our ancestors to reduce the risk of these undesirable qualities showing up in our population by correcting them. In other words, by editing humanity.