‘Yes, ma’am.’

‘And you took little kids down there, kids as young as Ben and your own sister.’

Nikos shrugged, uncomfortable, but with a trace of defiance. ‘Yes, ma’am. But I’ve been going down there for years myself. They were safe with me. I was always safe.’

‘He has a point, Agnes,’ Lobsang said, annoyingly.

Agnes snapped, ‘Tell me later when I figure out how much harm has been done.’

They came to the Poulson house, with its half-finished, broken-down stockade, the abandoned fields where saplings sprouted enthusiastically, and the house itself, whitewash peeling, an old swing on the porch choked by a vigorous vine. Only the door looked as if it had been recently used, some of the litter on the porch kicked aside to allow access.

Agnes asked, ‘So, Nikos, do we go in the door?’

‘You need to come round back.’

At the rear of the house was a pit, roughly dug into the thin strip of ground between the house itself and the stockade. It looked maybe eight feet deep. The ground around it was clear of the immature ferns that choked the rest of the area.

Lobsang looked into the pit. ‘A cellar? But it’s obviously unfinished. And there’s a hole in the side wall.’ He glanced at Nikos. ‘Leading to what?’

‘I thought you wanted me to show you, not tell you,’ Nikos said with a trace of cheek. He turned to his dog. ‘Rio, down. Rio – stay.’ The dog, panting, curled up in a bit of shade, tongue out, watching the action. Nikos ruffled her head. ‘She’ll be asleep in a minute.’ He slipped his pack off his back, opened it, and pulled out a smaller sack. It was lumpy, as if filled with rocks, and he tied this to his belt. Then he faced the adults. ‘Ready?’ He looked at Agnes. ‘You’re not scared, are you?’

‘Don’t get cocky,’ Agnes said. ‘Nikos, why don’t you lead? I’ll go second. George, you can be rear gunner.’

‘Who put you in charge?’

‘You did twenty years ago, when you brought me back,’ she said softly, with an eye on Nikos. ‘So, did you bring the flashlights?’

The passage down the sloping shaft that led from the ‘cellar’ was easy enough. In the years they’d been coming down here Nikos and his little buddies had dug in hand- and footholds.

But both Lobsang and Agnes were astonished when they climbed stiffly out of the shaft, and found themselves standing in a long, low chamber, lit only by their flashlights: a floor of trampled dirt, a smooth roof supported by pillars of rock or dirt. All this was evidently deep underground.

Agnes asked, ‘What is this place?’

‘I don’t know,’ Nikos said. ‘Something to do with the silver beetles. I call it the Gallery. Because it’s like a gallery in a big museum in a picture book my Mom used to read with me when I was little.’

He sounded different now, Agnes thought, in this echoing space, his face half-shadowed in the light of the flashes. Not so ashamed of the stunts he’d pulled. More like he was proud of what he’d found. Well, maybe he should be, she thought. She supposed he should have told people about this, but to have kept his nerve and go exploring in the first place was something.

‘It’s no gallery,’ Lobsang said. ‘Some kind of mine – and worked out, it looks like.’ He splashed his light on the roof, the floor. ‘An iron ore seam? This area’s rich in ore, it’s one reason New Springfield was planted here. But I’m not aware of any large-scale works here, apart from a few minor scrapes for the forges.’

‘This is more than a minor scrape, George.’

‘I can see that. So, Nikos, what about these silver beetles of yours?’

‘Turn around,’ said Nikos softly.

‘What’s that?’

‘Turn around.’

Agnes and Lobsang turned, swinging their flashlights.

The beetle was here.

As their lights splashed on it, it unpeeled from the ground, standing on a cluster of hind limbs, its black carapace gleaming with silver insets, and semi-transparent sacs of some kind of gas clustered on its exposed, greenish underside. It was the size of a human.

And a kind of face, half-hidden behind a silver mask, swivelled to consider them.

Agnes was astounded, overwhelmed. Whatever she had been expecting it hadn’t been something so utterly alien. She shrank back, would have fled if Lobsang had not held her.

‘Stay calm, Agnes.’

‘I am calm, Lob—George. I am calm. What the hell is it?’

Lobsang held his hands up to show they were empty, and carefully walked around the creature.

The beetle stood passively before Nikos, who had unwrapped his pack to reveal chunks of rock of various sorts, some hard like granite, some softer sandstone. Boy and beetle were a silent tableau while Lobsang inspected them.

‘I’ve known people who’ve travelled to the ends of the Long Earth,’ Lobsang said softly as he walked. ‘I’ve travelled pretty far myself. But I never heard of anything like this.’

Nikos grinned. ‘There’s plenty more where he came from.’

‘How do you know it’s a he?’

‘I don’t imagine Nikos does, for sure,’ Agnes said testily.

‘Agnes – just tell me what you see.’

‘Like an insect,’ she said immediately. ‘It is like a beetle. That black shell stuff that covers it looks segmented. I can’t count how many legs it’s got. Legs, or arms. Maybe it’s more like a centipede?’

‘I don’t think it matches any class of creature known on Earth. Or on the Long Earth, in any working-out of terrestrial evolution. Not even the intelligent crustaceans Maggie Kauffman found during her journey of exploration aboard the Armstrong II.’

‘Something new, then,’ Agnes said.

‘Or something not from here. Not from any Earth. Damn it,’ he said with sudden petulance, ‘I don’t want this to be happening. I don’t want mystery. I wish you hadn’t brought me down here!’

‘You don’t wish that at all, George.’

He sighed. ‘OK. What about the silver?’

Agnes looked closely. ‘I see … belts. A kind of sash, slung across its upper body. Little studs that seem to be stuck in the, umm, carapace. Things like bangles on some of the limbs – just like the bracelet Ben came home with. And that mask, of course. The head, George. The head looks almost human, apart from the eye.’

‘Eerie, isn’t it? Probably a coincidence of form.’

His lecturing tone irritated her. ‘Well, you don’t know anything at all, George, not yet. But maybe Nikos does. Nikos, can you talk to this thing?’

‘No,’ Nikos said firmly. ‘I’ve never heard them make a sound. Except for a kind of scraping when they walk. That’s their armoured bodies, I reckon. Some of them fly. Their backs open up and wings unfold. When they fly, they kind of rustle.’

Somehow, illogically, that detail made Agnes shudder.

Nikos said, ‘But you see more of that in the Planetarium. Not here.’

Lobsang said, ‘The Planetarium? … Never mind. Tell us later. OK, you don’t speak to them. So tell me what you’re doing with those rocks.’

‘I swap them for the silver things. The rings, the pendants. We pick up bits of rock from the ground, all around the forest, and we bring them here. If we’re doing it properly we have to show them where we found the rocks on a map. I say map. It’s just a kind of scribble I drew once.’

‘You’re swapping rock samples for silver artefacts?’

‘I guess you could call it that.’

Agnes asked, ‘If you can’t speak to them, how did you work all this out? The whole idea of the trade.’

Nikos seemed irritated at having to be quizzed like this, in his own little empire. ‘It took a long time. It started with a bit of quartz I had in my pocket, one of the first times. I just showed it to one of them. After that—’

‘Never mind,’ Lobsang said. ‘Agnes, I guess the truth is nobody told this smart kid that communication between such divergent life forms was impossible, so he just went ahead and did it anyhow. But why would they want rock samples? Well, because they want to do some more mining, I guess. They need to study the landscape. But to what end? …’