When I heard the first scream, I turned away and covered my ears with my hands, pressing hard until my head hurt. At that moment I could do nothing to help. But I could still hear it, the sound of a priest in torment, and it went on for a long time before finally fading away.

So I shivered in the dark barn, listening to rain drumming on the roof, trying to gather my courage. It was a bad night and it was about to get worse.

Ten minutes later, when the rigger and his mate arrived, I rushed across to meet them in the doorway. Both of them were big men and I barely came up to their shoulders.

‘Well, lad, where’s Mr Gregory?’ asked the rigger, an edge of impatience in his voice. He lifted the lantern he was holding and peered about suspiciously. His eyes were shrewd and intelligent. Neither of the men looked like they would stand any nonsense.

‘He’s been taken badly,’ I said, trying to control the nerves that were making my voice sound weak and wobbly. ‘He’s been in bed with a bad fever this past week so he’s sent me in his place. I’m Tom Ward. His apprentice.’

The rigger looked me up and down quickly, like an undertaker measuring me up for future business. Then he raised one eyebrow so high that it disappeared under the peak of his flat cap, which was still dripping with rain.

‘Well, Mr Ward,’ he said, an edge of sarcasm sharp in his voice, ‘we await your instructions.’

I put my left hand into my breeches pocket and pulled out the sketch that the stonemason had made. The rigger set the lantern down on the earthen floor and then, with a world-weary shake of his head and a glance at his mate, accepted the sketch and began to examine it.

The mason’s instructions gave the dimensions of the pit that needed to be dug, and the measurements of the stone that would be lowered into place.

After a few moments the rigger shook his head again and knelt beside the lantern, holding the paper very close to it. When he came to his feet, he was frowning. The pit should be nine feet deep,’ he said. “This only says six.’

The rigger knew his job all right. The standard boggart pit is six feet deep but for a ripper, the most dangerous boggart of all, nine feet is the norm. We were certainly facing a ripper – the priest’s screams were proof of that – but there wasn’t time to dig nine feet.

‘It’ll have to do,’ I said. ‘It has to be done by morning or it’ll be too late and the priest will be dead.’

Until that moment they’d both been big men wearing big boots, oozing confidence from every pore. Now, suddenly, they looked nervous. They knew the situation from the note I’d sent summoning them to the barn. I’d used the Spook’s name to make sure they came right away.

‘Know what you’re doing, lad?’ asked the rigger. ‘Are you up to the job?’

I stared straight back into his eyes and tried hard not to blink. ‘Well, I’ve made a good start,’ I said. ‘I’ve hired the best rigger and mate in the County.’

It was the right thing to say and the rigger’s face cracked into a smile. ‘When will the stone arrive?’ he asked.

‘Well before dawn. The mason’s bringing it himself. We have to be ready.’

The rigger nodded. ‘Then lead the way, Mr Ward. Show us where you want it dug.’

This time there was no sarcasm in his voice. His tone was business-like. He wanted the job over and done with. We all wanted the same, and time was short so I pulled up my hood and, carrying the Spook’s staff in my left hand, led the way out into the cold, heavy drizzle.

Their two-wheel cart was outside, the equipment covered with a waterproof sheet, the patient horse between the shafts steaming in the rain.

We crossed the muddy field, then followed the blackthorn hedge to the place where it thinned, beneath the branches of an ancient oak on the boundary of the churchyard. The pit would be close to holy ground, but not too close. The nearest gravestones were just twenty paces away.

‘Dig the pit as close as you can get to that,’ I said, pointing towards the trunk of the tree.

Under the Spook’s watchful eye I’d dug lots of practice pits. In an emergency I could have done the job myself but these men were experts and they’d work fast.

As they went back for their tools, I pushed through the hedge and weaved between the gravestones towards the old church. It was in a bad state of repair: there were slates missing from the roof and it hadn’t seen a lick of paint for years. I pushed open the side door, which yielded with a groan and a creak.

The old priest was still in the same position, lying on his back near the altar. The woman was kneeling on the floor close to his head, crying. The only difference now was that the church was flooded with light. She’d raided the vestry for its hoard of candles and lit them all. There were a hundred at least, clustered in groups of five or six. She’d positioned them on benches, on the floor and on window ledges but the majority were on the altar.

As I closed the door, a gust of wind blew into the church and the flames all flickered together. She looked up at me, her face running with tears.

‘He’s dying,’ she said, her echoing voice full of anguish. ‘Why did it take you so long to get here?’

Since the message reached us at Chipenden, it had taken me two days to arrive at the church. It was over thirty miles to Horshaw and I hadn’t set off right away. At first the Spook, still too ill to leave his bed, had refused to let me go.

Usually the Spook never sends apprentices out to work alone until he’s been training them for at least a year. I’d just turned thirteen and had been his apprentice for less than six months. It was a difficult, scary trade, which often involved dealing with what we call ‘the dark’. I’d been learning how to cope with witches, ghosts, boggarts and things that go bump in the night. But was I ready for this?

There was a boggart to bind which, if done properly, should be pretty straightforward. I’d seen the Spook do it twice. Each time he’d hired good men to help and the job had gone smoothly. But this job was a little different. There were complications.

You see, this priest was the Spook’s own brother. I’d seen him just once before when we’d visited Horshaw in the spring. He’d glared at us and made a huge sign of the cross in the air, his face twisted with anger. The Spook hadn’t even glanced in his direction because there’d been little love lost between them and they hadn’t spoken for over forty years. But family was family and thafs why he’d eventually sent me to Horshaw.

‘Priests!’ the Spook had raved. ‘Why don’t they stick to what they know? Why do they always have to meddle? What was he thinking of, trying to tackle a ripper? Let me get on with my business and other folks get on with theirs.’

At last he’d calmed down and spent hours giving me detailed instructions on what had to be done and telling me the names and addresses of the rigger and mason I had to hire. He’d also named a doctor, insisting that only he would do. That was another nuisance because the doctor lived some distance away. I’d had to send word and I just hoped that he’d set off immediately.