At last, we reach the Mississippi and ride down the slope into the bone-dry riverbed.

Seeing the impact that the war has had on the Mississippi is truly awful. I hate what our species has done to the world, the ways in which it has destroyed nature. My only hope is that one day our country will recover, that the Mississippi will be the beautiful, life-giving river it once was.

“What’s that noise?” Ryan says, breaking me from my thoughts.

I strain to hear over the rumble of the engine. I can just about pick up a noise, a sort of whining. It sounds like a vehicle revving.

“It’s the other car, isn’t it?” I say.

Through the darkness, I can just make out Ryan shaking his head. My blood runs cold.

All at once, a blinding light suddenly appears in the rearview mirror. My heart clenches as I realize we’re not alone, that someone’s been following us.

Suddenly, our car’s shunted forward. I scream and grab hold of my seat as we jerk roughly around. Ryan fights to keep hold of the steering wheel, to keep control. But whatever hit us rams into us again. I can’t see through the bright light, I can’t tell what’s hitting us. But there’s no chance to work it out, because we’re hit again and suddenly we’re spinning, up and over, round and round.

Charlie and Bree are screaming as we spin. My body feels like it’s being hurled through the air.

Then, suddenly, my head slams against the window. I hear a crack. Before I get the chance to work out if it’s the glass or my skull, everything turns black.

PART THREE

CHAPTER FIFTEEN

I groan. My head is pounding. I manage to open my eyes a sliver. The daylight is stark and bright, making me wince. I realize my face is against a hard cement ground covered in sand.

Memories of the car crash come back to me in a rush. I sit up, startled. As I do, I hear the distinctive clinking noise of chains.

I look all around. I’m in a bare cell filled with other people. We’re all sitting on the dusty ground, chained to the wall. There’s a window set high in the bricks, letting in the blistering sunshine. We’re definitely still south, but where exactly is a question I cannot answer.