Blinking in the sunlight, I look around. The line of trees stretches out either side of me. Behind me is the barren, grey wasteland. Running my tongue around my mouth, there is a faint residue of the stuff I ate before.

‘Where are we?’ I ask.

‘This, my friend, is the perimeter woodland of Earth Zone. Five hundred metres thick, and stretching for a few kilometres in each direction.’

I stand up and step out of the craft, flexing my elbow and wincing. It has swollen up badly while I was asleep, but I am much more interested in the woods directly in front of me.

‘Wow. These are the first trees I’ve seen here. Well, the first normal ones.’

‘That’s because they are pretty much the only ones. They’re confined to the Earth Zone, where they can grow wild and … kinda messy. Other than here, we haven’t had trees growing wild since the Big Burn.’

Even so, there’s something not quite right about the forest. It’s too dry. There are patches of brown on the trees and the ground is brown and grey rather than green and lush.

‘Why is it so dry?’

‘Drought season. All of the weather inside the zone is controlled. They experiment with different extreme conditions, you know? Heavy snow, excessive rainfall, that sort of thing.’

I step forward and Philip says, ‘No further. The whole thing is protected by a … by a … what would you say? A Proton-positive Force Field?’

I shrug. ‘I guess. An invisible shield?’

‘Yes. Exactly. You might want to watch that chicken. The reason we are here is that there is a temporary gap in the force field, created by Kallan a few days ago. Think of it like cutting a hole in a chain-link fence. But I don’t think your chicken knows where the gap is.’

Suzy is pecking the ground and getting closer and closer to the trees. In the next second she does her little hop-flap and gets much too near.

I call out, ‘Suzy!’ and, without thinking of the possible consequences, I run towards her.

Big mistake. She doesn’t know me like she knows Iggy, and as I approach with my arms outstretched to grab her, she leaps away in alarm, flaps her wings and heads straight for the trees.

‘No, Suzy! Stop!’ I shout.

It’s too late. There’s a flash of white light and a sizzling noise where she hits the force field.

To my horror, instead of bouncing off, as though she has hit a wall, the speed of her approach carries her through, towards the trees, and there is a pitiful squawk as a flaming, smouldering ball of feathers hits the ground and rolls and rolls out of sight into the undergrowth.

‘No! No! Suzy!’

I want to run forward to get her, but I can feel the prickling of the force field and I have to retreat. I slump on to the ground in dismay. In trying to save her, I have killed my best friend’s pet. I scan the branches and undergrowth and all I can see is little wisps of smoke, and a lick of flame here and there where Suzy’s burning feathers caught the bone-dry leaves on the ground.

‘I’m sorry, Ethan,’ says Philip’s voice from behind me. For a bot, he sounds pretty genuine.

Getting wearily to my feet, I stare angrily at the place where poor Suzy hit the shield – there is still a whitish patch where she went through – and in frustration I pick up a stone and throw it hard. It sails through the patch and pings off a tree, and then the white patch slowly disappears, closing up as though it is healing.

If I am expecting this to make me despair, however, it doesn’t. Something changed in me earlier when I decided that I would get Tammy and Iggy back. The death of a chicken is not going to stop me.

‘Philip?’ I say. ‘How do I get in there?’

‘I like your style, captain,’ says Philip. ‘Like I say – there’s a gap. If we can find it. Or you may wanna try the main entrance. It’s the only other way.’

Having seen the fate of Suzy, I am not at all keen on trying the force field, gap or no gap.

‘It’s got to be the main entrance, I think,’ I say.

‘OK, pardner,’ says Philip.

Then I look down at myself. Jeans, trainers, woolly sweater. I look nothing like an Anthallan. There is no way I can just walk up to the entrance.

‘But how am I going to manage that?’ I ask.

‘By listening to your Uncle Philip, that’s how. Right now, though, we have to go. We can assume that a sudden breach of the force field will result in an investigation. We don’t wanna hang around here, kid.’