In the odd light, her face was set into an expression that Tom recognised. It showed the will that had taken her into the farm, the will that had made her disobey her parents. ‘You can’t stop me.’

And so they went onwards. Zita would close her eyes and go limp, and send herself a few hundred feet ahead, trying to conserve as much of her energy as she could.

Whilst she was gone, Tom would stand, supporting both his friends, enveloped by blackness, staring only at the light from his tiny lamp. He tried to keep his mind focused on the flame, and ignore the emptiness surrounding him.

It was so much worse than being on the boat. He wondered if death was like this, and his mind kept edging towards despair.

Zita would then return. Each time she was noticeably weaker. The fourth time she did it, it took her a long time to get back to normal, during which Tom began to think that they all might turn to ice. He had no idea how much time was passing. It seemed sometimes to be hours.

‘You’ve got to help me, Kit,’ he said. ‘Please.’

But Kit did not respond.

When she next returned, she could barely walk. ‘It’s not far off,’ she said and then stumbled and fell.

Tom grabbed her. ‘Come on, Zita, you can do it.’

Kit sat down on the ground.

‘I can’t do this on my own! Please, Kit, please!’

There was a rumbling sound, coming from somewhere far away.

‘I think,’ whispered Zita, ‘that means he’s noticed.’

Tom put Zita’s arm over his shoulder and grabbed Kit by the arm. The boy got up sluggishly.

‘I will face the Captive. Rather her than him again.’

Tom squeezed his arm in thanks.

The three of them half-ran, half-stumbled, in a straight line, through the cold, the rumbling behind them growing, now seeming like a human roar of rage.

There was a burst of light behind them, illuminating the nothingness, showing a great wide plain.

Near in front of them was the darker blackness, the anomaly that Zita had noted.

‘Jack’s in the house. The … thing … it’s just ahead …’ slurred Zita. She could hardly move. ‘Go, Tommy, go. Leave me here. I’ll do it one more time. It will stop him for a bit.’ She was wilting, her knees bent. Tom grabbed her, though he was fading too.

His whole body felt weak, as if he’d been climbing a mountain. The air was thin. Every gulp of breath cost him. He faltered.

The light focused into a beam and started to track across the wasteland. Zita shook and went limp.

The light behind them paused. Tom and Kit pushed themselves onwards, dragging Zita between them.

A sudden spasm shook the girl, and Zita came spluttering back. ‘He saw me. He’s furious.’ She was shaking with cold and fear.