Suddenly she’s overcome by a strange sensation, as though her mind has lost control of her body. It’s happened to her several times in the past when she’s been stressed out or suffered a shock.

Before she knows it, she’s off the bed and heading for the door. She doesn’t want to break the news to her husband over the phone. She needs to tell him to his face. She’ll then know from his reaction if she’s lost him forever as well.

Mary is on autopilot as she drives towards Oaktree Farm. She’s numb with grief, shock and self-recrimination, and is only half-aware of the road in front of her.

But she’s stopped crying and feels a peculiar need to act normal, to put on a brave face, as though nothing bad has happened.

Maybe it’s all in her head anyway. A grim nightmare from which she will eventually emerge.

It’s a thought that flashes through her mind but doesn’t take root. How can it when she knows only too well that she’s awake? The pain she feels is real and so is the sun that’s shining down on the countryside around her.

She starts to hum a meaningless tune in an effort to drown out the shrieking noise in her ears. And she keeps it up until she reaches her destination.

Oaktree Farm.

Robert’s car is parked in the front yard next to the barn, and the sight of it brings on a violent urge to vomit. But somehow she manages to hold it in as she pulls her own ageing Vauxhall Corsa to a stop behind it.

The moment she kills the engine she hears a voice and turns to look through the side window.

Amanda Roth, Simon’s wife, is standing at the top of the short flight of stairs that leads down to the cellar door. She’s waving an arm and her voice carries through the glass.

‘Hi there, Mary,’ she calls out. ‘I thought it was Simon and Robert returning from the shoot. I’m tidying up in the cellar. Come and join me.’

Amanda disappears back down the cellar steps and Mary struggles to decide what to do.

Robert isn’t here so she’s going to have to tell Amanda what has happened. But she doesn’t want her friend to know. Or anyone else other than her husband.

She sits there without moving for perhaps a minute, her chest pumping, starved of oxygen. Eventually, as though in a trance, she pushes the door open and gets out. It feels almost as though her mind is detached from her body as she walks across the yard and down into the cellar. She’s never been in there before and it’s brighter than she imagined it would be thanks to the light on the ceiling.