She takes it out of her zipped fleece pocket. She is not wearing gloves, and the moment it touches her skin, she feels a zing of energy pulse through her. It makes her hesitate. She begins to doubt her ability to control its force, to steer its power in the direction she needs it to go. In the kitchen she had marshaled it, had mastered it, but only just. And that was at home. This time she is standing in the grave of someone who wishes her ill. Her running clothes are properly saturated now, and she starts to shiver.

‘This is rubbish,’ she declares. ‘I’m cold, I’m tired and I’m scared. Let’s get this thing done.’

So saying, she shoves the torc over her wrist. It catches on the fluffy thickness of her fleece, so that she can jam it no farther than her wrist. She hopes it will stay in place. All at once there comes the swirling sensation, as if she is on a fairground ride, and everything around her blurs and spins. She plants her feet firmly on the uneven ground, taking hold of the pickax once more. This time, colored light pulsates in front of her.

Wow. This is what I imagine a bad trip feels like. Okay, just ignore it; stay focused.

As she slides the iron spike under the stone she can hear her own heartbeat echoing in her ears, pounding erratically and at a worrying speed. She tries to ignore it, pulling all her attention to shifting the heavy weight at her feet, willing herself to use whatever it is that is inside her.

‘Come on!’ she shouts through the lashing rain. Setting her teeth, she hauls on the ax handle. ‘Move, you bloody piece of … Move!’

There is a grating noise, rough stone sliding over grit and mud and bone, and then it is done. The momentum of the slab’s own weight once it is in motion carries it over the edge of the grave so that it slews sideways into the dirt. And the tangled skeleton, twisted and broken, is exposed.

Tilda is just on the point of crouching down, reaching her hand toward the dark, stained bones, when she is knocked off her feet. She is flung backward, and lands heavily on the hardest, stoniest part of the trench. Winded, unable to draw a breath, the air driven from her lungs by the force with which she struck the ground, she clutches at her chest, struggling to make her body work again and take in oxygen. As she thrashes about in the freezing earth she turns onto her stomach, pushing herself up onto her knees, and all the time she can feel it coming, can feel the rotten soul of the long-dead witch in the grave rising up to loom over her.