‘Shrieking in the woods, white figures moving through the trees,’ she said. ‘What would the folklore say, Ben?’

If he’d been talking to anyone else, Cooper might have mentioned corpse candles. It was the name given to a flame or ball of light seen travelling above the ground on the route from a cemetery to a dying person’s house and back again. For some reason the light was usually blue. A similar light appearing in a graveyard was believed to be an omen of approaching tragedy. Cooper seemed to recall that they appeared on the night before a death. The stories told about corpse lights were like those of the will-o’-the-wisps, mischievous spirits who attempted to lead travellers astray.

As Diane Fry would certainly have pointed out, there were always logical explanations for these things. Anyone observing a will-o’-the-wisp might be seeing nothing more than a luminescent barn owl. A wildlife officer had once told him that some barn owls possessed a form of bioluminescence caused by honey fungus. The white plumage of the birds could look eerie enough at night, if you glimpsed one in your torchlight. A luminescent barn owl flitting through the darkness would be enough to spook anyone. And corpse candles? Witnesses might just have been noticing the effect of methane gas, the product of decomposing organic material in marshes and peat bogs.

But even in the twenty-first century, the prosaic scientific explanations weren’t always what people wanted. Everyone liked a bit of mystery. Generation after generation, the more superstitious inhabitants of Derbyshire had preferred to believe in spirits.

‘Who told you that anyway?’ asked Cooper.

‘DC Villiers. I heard about the statements from your members of the public this morning.’

‘Oh.’

‘Have you got a problem with that? We’re colleagues, aren’t we? We should be working together.’

‘If you say so.’

Cooper stopped. He’d caught a glimpse of something blue glittering among the trees, a flash of light, as if from a piece of glass reflecting the sun. The sight was irresistible, a signal tempting him from the path. He had no option but to turn aside and investigate.

When he got closer he could see that what he’d seen was a ball of smoky blue glass, the kind of thing sold in craft centres and gift shops for use as a table ornament or a flower vase. His sister would have taken it home and placed a scented candle inside it.

But inside this one was a tangle of threads. There were lengths of cotton of every colour – not only white and black threads, but bright strands twisted among them in no discernible pattern. It was just a random hotch-potch of colour, all given an eerie glow by the blue of the glass. The neck of the ball was attached to a branch of a rowan tree by a pair of ribbons and it moved slightly in the breeze, spinning one way and then the other. It had been placed at a height just above Cooper’s head, but he could reach up to stop its movement. Then he saw the scraps of paper entangled among the threads, rolled into little tubes and thrust into the multicoloured mass.

‘What is it?’

Cooper turned at the sound of Fry’s voice. As happened so often, her words intruded like a cold dose of reality from the outside world at a moment when he was contemplating the mysteries of the rural imagination, feeling the centuries of belief in magic running disturbingly through his veins. There was something about these old superstitions that made him shiver, not only with apprehension, but with understanding too.

‘You don’t want to know, Diane,’ he said.

‘I suppose that means it’s something absurd and rustic.’

‘Well, it’s a witch bottle,’ said Cooper.

Fry snorted. ‘Exactly.’

Cooper looked at her, not at all surprised this time that she’d noticed him leaving the path and decided to follow him. It was like being under twenty-four-hour surveillance. He wondered what she would have done if he’d simply sneaked off to relieve himself behind a tree. Would she have stood there making notes?

‘It should probably be called a “watch ball” actually,’ he said. ‘It’s used to guard against evil spirits. Its purpose is to draw in and trap negative energy that might have been directed at its owner. It can counteract spells cast by witches or prevent spirits moving about at night. That’s why it’s placed here, by the coffin road, because it’s the route spirits would take. It’s a sort of diversion sign, to deflect evil and keep it away from something, or someone.’

Despite her initial reaction, Fry was peering more closely into the blue glass as Cooper held it still. ‘So the pieces of paper inside?’

‘Charms,’ said Cooper. ‘If we can get them out and interpret them, they might give us an idea what evil the witch bottle is designed to counteract and who the charms might be aimed at. And perhaps who put them here.’

‘Well, that sounds like a job for a superstitious country boy,’ said Fry. ‘I wonder where we’d find one of those.’

Carefully, Cooper began to untie the ribbons from the branch and reached out to grasp the ball.

‘Fingerprints,’ said Fry automatically.

‘You’re right, of course.’

Cooper found a fresh pair of latex gloves in his pocket and pulled them on before handling the ball. It was surprisingly light. The glass must be very thin, he supposed.

‘What’s in the ball?’ asked Fry. ‘What are all those bits of paper?’

Cooper couldn’t make out the language written on them or interpret the symbols. But he had a good idea what they would be.

‘Spells,’ he said. ‘Probably curses.’

‘Oh, right.’

And there was something else shoved right into the middle. A piece of clay, formed into a distinctive shape. Not human, though. A bird.

‘Now that I recognise,’ said Fry. ‘It’s an eagle’s head.’

‘Yes.’

‘Does it have some significance?’ she asked.

‘Around here it does.’

Cooper placed everything into evidence bags for the forensic examiner. As he turned the ball in his hand, he wondered how the colour was introduced into the glass when it was made. The swirls of blue looked so in- substantial and translucent. They could almost have been tiny evil spirits themselves, trapped in the surface of the bottle.

15

Ben Cooper parked his Toyota outside Earl Sterndale’s best-known landmark – its pub, the Quiet Woman. The swinging wooden sign outside was much photographed by tourists in the summer, because it showed an image of a headless woman. According to the story behind the pub’s name, that was a previous landlord’s solution to the problem of keeping his garrulous wife quiet.

There was a campsite next to the pub, though it was empty. Marston’s Burton Ales. Outside the door stood an old sink and a brush for boot washing, and plastic bags were kept in the porch for walkers to put over their dirty boots before entering the pub. It was the same principle as the one used at crime scenes, where forensic examiners and police officers wore plastic overshoes to avoid contaminating the scene with trace evidence and footwear marks.

The pub had milk delivered from a dairy in Hazel Grove. The bottles were still sitting in the porch, even though it was past midday. Of course, the Quiet Woman was closed. Many landlords in the more outlying villages found there was no point in opening their pubs during the day, especially in the winter months. There just wasn’t enough lunchtime trade to pay for the overheads.

Cooper looked across the road to locate the Beresfords’ house. Luke Irvine would be unhappy that his DS seemed to be covering the same ground, as if Irvine hadn’t done a good enough job the first time round. But that couldn’t be helped. Not today. It was bad enough having Diane Fry tagging along like a spare part. Didn’t she have anything better to do with her time? He supposed he could ask her, but he would only get a sarcastic answer.