Nick waved and forced himself to take a few shambling steps to Tim, though he had to clutch at the wall in the last second to stop himself from falling.

“You have to stop him, Nick!” Tim exclaimed. He didn’t look at Nick but everywhere else, his eyes flickering fearfully from side to side. “Whatever he’s doing... you’re both doing... it’s wrong!”

“What?”asked Nick wearily. The walk had tired him and one of the internal voices had become stronger. “What are we doing? It’s a scientific experiment, that’s all. And who is the him I have to stop? I’m in charge here.”

“Him! Hedge!” blurted Tim, pointing back towards the hemispheres, where the fog was thickest. “He killed my workmen, Nick! He killed them! He pointed at them and they fell down. Just like that!”

He mimicked a spellcasting movement with his hand and started to sob, without tears, his words tumbling out in a mixture of gasps and cries.

“I saw him do it. It was only – only...”

He looked at his watch. The hands were stuck in place, stopped for ever at six minutes to seven.

“It was only six to seven,” whispered Tim. “Robert saw the coasters coming in and woke us all up, so we could celebrate the completion of the work. I went back to the hut for a bottle I’ve been saving... I saw it all through the window—”

“Saw what?” asked Nick. He was trying to understand what had upset Tim so much, but there was an awful pain in his chest and he simply couldn’t think. He couldn’t put the concept of Hedge together with Tim’s murdered workers.

“There’s something wrong with you, Nick,” Tim whispered, crawling back away from him. “Don’t you understand? Those hemispheres are pure poison and Hedge killed my workmen! All of them, even the two apprentices. I saw it!”

Without warning, Tim suddenly retched violently, coughing and gasping, though nothing came out. He had already thrown everything up.

Nick watched dumbly, as something inside him revelled at this news of death and misery and an opposing force writhed against it with feelings of fear, revulsion and terrible doubt. The pain in his chest redoubled and he fell down, clawing at his heart and his ankle.

“We have to get away,” said Tim, wiping his mouth with the back of one shaking hand. “We have to warn somebody.”

“Yes,” whispered Nick. He had managed to sit up but was still hunched over, one pale hand over his heart, the other clutching the fragment of wind flute through his trouser cuff. He fought against the pain in both places and the pressure in his head. “Yes – you go, Tim. Tell her... tell them I’ll try and stop it. Tell her—”

“What? Who?” asked Tim. “You have to come with me!”

“I can’t,” whispered Nick. He was remembering again. Talking to Lirael in the reed boat, trying to keep the shard of the Destroyer within him at bay. He remembered the nausea, and the metallic bite on his tongue. He could feel it again now, rising up.

“Go!” he said urgently, pushing at Tim to make him go away. “Run, before I— Aah!”

He stifled a scream, fell down and curled into a ball. Tim crawled around to him and saw Nick’s eyes roll back. For a moment he contemplated picking him up. Then he saw the white smoke trickling out of Nick’s slack-jawed mouth.

Fear overcame everything then and he started to run, between the lightning rods, up the hill. If only he could get over the ridge, get out of sight. Away from the Lightning Farm and the steadily rising fog...

Behind him, Nick’s hand gripped his trouser cuff even more tightly. He was whispering to himself, jumbled words spilling out in a frenzy.

“Corvere capital of two million principal products manufactured banking the attraction between two objects is directly proportional to the product of the day breaks not it is my heart four thousand eight hundred and the wind shifts generally in direction white wild Father help me Mother Sam help me Lirael—”

Nick stopped, coughed and drew breath. The white smoke drifted off into the fog and no new smoke emerged. Nick drew in two more shaky breaths, then experimentally let go of his trouser cuff and the piece of wind flute inside it. He felt a chill run through his body as he let go, but he still knew who he was and what he must do. Using the corner of the building, he hauled himself upright and staggered off into the fog. As always, the silver hemispheres glowed in his mind, but he had forced them into the background. Now he was thinking of the blueprints of the Lightning Farm. If Tim had made it according to Nick’s design instructions, then one of the nine electrical junction boxes would be just around the corner of the main mill building.

Nick almost ran into the western wall of the mill, the fog was so thick. He skirted around it to the north as quickly as he could, staying away from the southern end, where the Dead laboured to lift the first hemisphere on to a flat-bed railway wagon.

The hemispheres. They glowed in Nick’s mind brighter than the lightning flashes. He was suddenly struck with a compulsion to make sure that they were properly lifted into the cradles, that the cables were correctly joined, the track sanded for traction in this wet fog. He had to see to it. The hemispheres had to be joined!

Nick fell to his knees on the railway, and then forward, to lie curled up across the cold steel and the worn wooden sleepers. He clutched at his trouser cuff, fighting against that overwhelming urge to turn right and go over to the hemisphere on its railway wagon. Desperately he thought of Lirael lifting him into the reed boat, of his promise to her. His friend Sam, picking him up after he’d been knocked out by a fast ball playing cricket. Tim Wallach, bow-tied and dapper, pouring him a gin and tonic.

“Word of a Sayre, word of a Sayre, word of a Sayre,” he repeated over and over again.

Still mumbling, he forced himself into a crawl. Across the track, ignoring the splinters from the old railway sleepers. He crawled to the far side of the mill and used the wall to half crawl, half stumble down to the junction box, which was actually a small concrete hut. Here, hundreds of cables from the lightning rods fed into one of the nine master cables, each as thick as Nick’s body.

“I’ll stop it,” he whispered to himself as he reached the junction box. Deafened by thunder, half-blind from the lightning, and crippled by pain and nausea, he reached up and tried to open the metal door that was marked with a vivid yellow lightning bolt and the word DANGER.

The door was locked. Nick shook the handle, but that small act of defiance did nothing but use up his last store of energy. Exhausted, Nick slid back down and sprawled across the doorway.

He had failed. Lightning continued to spread up the slope, accompanied by fog and booming thunder. The Dead continued to struggle with the hemispheres. One was on its railway wagon, which was being moved along the rails to the far end of the line, even as the Dead who pushed it were struck again and again by lightning. The other hemisphere was swinging off the coaster – till lightning burnt the rope and it came crashing down, crushing several Dead Hands. But when the hemisphere was raised, the crushed Hands came slithering out. No longer recognisable as anything remotely human, and no use in the work, they squirmed their way east. Up the ridge, to join the Dead that Hedge had already sent to make sure that the final triumph of the Destroyer was not delayed.

“You have to believe me!” exclaimed Sam in exasperation. “Tell her again that I promise on the word of a Prince of the Old Kingdom that every single one of you will be given a farm!”

A young Southerling was translating for him, though Sam was sure that like most Southerlings, the matriarch understood at least spoken Ancelstierran. This time she interrupted the interpreter halfway through and thrust the paper she held out to Sam. He took it and quickly scanned it, acutely aware that he had only a minute or two left before he had to go back to Lirael.