And above them, the storm gathered itself, ready for its final onslaught.

He glanced behind as they reached the line of tumbled stone. Close, too close.

‘Climb,’ he said, and swung around.

Stanislav rose above him, and he held out the knife. As inadequate as it seemed, the tentacles reared away from it and tried to come at him from the sides. Dalip slashed at the air to keep them away, and gain time for Mary to get clear.

It was impossible to tell whether Stanislav was actually frightened of the knife, or whether he was simply playing. Dalip didn’t think he’d wounded him. But hurt him? Surprised him? Perhaps that.

The creature could simply fall on him, envelop him completely and tear him apart like he’d done to the guards. But it didn’t. Because some of its reactions were still human.

That insight might save him yet.

A block of dressed stone whirled past his ear. It was big, spinning, and not particularly fast, but Stanislav was too preoccupied to dodge it. It entered the central mass and disappeared. Then Stanislav was on the ground, surface churning as he tried to rid himself of this sudden cold, hard intrusion.

Dalip scrambled up the fallen arch to the top.

‘We can’t keep this up all night,’ said Mary.

There was blood coming from her mouth, and Dalip instinctively reached up to wipe it away.

She knocked his hand aside. ‘Bit my tongue, that’s all.’

They jumped down the other side. He was outside the crumbling castle’s walls for the first time, and looked back at his prison. He didn’t recognise it – it had seemed secure, and now it was a shambles of collapsed buildings and broken masonry.

Also, the rising tentacular creature lit by the burning sky.

‘I’ve got an idea.’

‘Is it really stupid?’ she asked.

‘Very.’

‘Okay,’ she said, and that was the last thing he heard her say for a while. The storm beat down at them with everything it had. The wind tore at them, strong enough to blast them with small sharp stones, and the lightning became a relentless static discharge above their heads.

Dalip raised his arm to protect his face and leant in hard, heading towards the flank of the mountain, to the edge of the bowl carved in it, and where it would be possible, perhaps, to climb to the summit.

After that, it was one foot in front of the other, the palms of his hands and the soles of his feet bleeding from each new cut as he reached up, pulled hard and dragged himself closer to the top. Mary, wearing the red dress, struggled, and he had to stop for her, wordlessly tell her to trust him, tell her that it would all be worth it in the end.