Claire drove as fast as she dared along the narrow lanes. She knew all the passing places, the sharp bends, the blind corners and junctions, and was able to dash to the office in town to collect the keys and still make it to the property before the client arrived.

Whatever happened, she’d be back home within the hour.

‘It’s a man viewing on his own, Claire.’ Even over the phone, she’d heard the guilt in Jeff’s voice – partly because he knew she was on annual leave, and partly because he never usually sent female agents to view with male clients they didn’t already know. He was old-fashioned like that. But he’d sounded desperate.

‘He’s a cash buyer,’ Jeff had added, offering to swap viewings with her, though the alternative was much further to drive. Claire opted for the quick job close to home.

Galen Cottage was as derelict as they came and had been on their books for over a year. She’d be glad to see the back of it, but with only two bedrooms and a roof that had more holes than slates, the remote cottage wasn’t getting any bites. She hoped this man wanted a project.

Claire parked up and unlocked the front door. Inside it smelt musty and damp, but that was to be expected; it hadn’t been lived in for years. As she waited for the client, she wrestled with a couple of warped windows to let in some air, but they wouldn’t budge. Years of paint and the salty sea air had made them stick fast.

‘Oh, come on,’ she said, glancing at her watch, pacing the small living room. ‘Don’t be late today of all days.’

She went upstairs and looked around. While she was up there, she thought she heard the crunch of gravel on the drive. She peered out of the tiny panes but saw nothing. She managed to force open the bathroom window, feeling slightly sick from the stench. The toilet wasn’t exactly going to help the sale, even if it was obvious that the whole place needed gutting.

She heard a noise downstairs.

Finally, she thought. If it wasn’t him, she’d call Jeff and ask for Mr Barrett’s number. She’d been in such a rush that she’d forgotten to make a note of it, but when she felt in her pocket she realised that she’d left her phone in the car.

‘Hello?’ she called out, wondering if he’d let himself in. She’d left the door wide open. She trod carefully on the steep stairs, going down to greet the client.

The narrow hallway was dark and gloomy – the electricity had been cut off years ago – and she kicked aside all the old mail and flyers lying on the grimy tiles. But there was no sign of anyone.

She put a hand on the front door, tugging on the handle, convinced she’d left it open. Perhaps he’d come in and had a quick look, seen the state of the place and left immediately. She pulled harder on the handle, but it wouldn’t move. ‘Damn this stupid house,’ she said, giving the door a kick.

‘Hello,’ she called out, her face close to the wood. ‘Anyone out there? Can you give the door a shove?’ She tried again, but when she bent down and peered through the gap, she could see it was more than stuck. It was locked.

‘What the hell…?’ She felt in her back pocket for the large, old-fashioned door key, but it wasn’t there. She dashed back upstairs to see if she’d left it in the bathroom, but she hadn’t. She froze in the bathroom doorway, staring at the window she’d opened only a couple of minutes before. It was now shut. The stench of drains was already building up again.

‘Christ,’ she whispered, hand over her mouth, slowly checking behind the door. She didn’t believe in ghosts but was willing to if it meant she wasn’t locked inside the cottage with a psycho.

Halfway down the stairs she stopped, suddenly remembering where the key was. She’d left it in the lock. On the outside. Back in the hallway, she glanced about nervously, wondering what to do. Habit made her reach into her pocket for her phone again – it was time to call Jeff – but of course, she’d left it in the car.

Then another noise. She couldn’t be certain if it had come from inside or outside.

‘You’re being silly,’ she tried to convince herself. The noise was most likely from a passer-by who had seen the door open and decided they should lock it. The locals looked out for one another around here, and she’d noticed the public footpath sign cutting across the driveway. No doubt loads of walkers came through. Claire almost burst with relief.

Then she heard a different noise – something that sounded too much like a floorboard creaking upstairs. Her skin prickled.

‘Hello? Who’s there?’ She reached for an old poker lying beside the fireplace and approached the bottom of the stairs. Jeff would be ecstatic if she bludgeoned a potential buyer. ‘Anyone up there?’ Her voice was croaky, loaded with fear.

The floor creaked again, as if someone was on the landing. She trod on the first step, her throat pulsing in time with her racing heart. She’d heard of estate agents getting into trouble on remote viewings. As she rounded the narrow dogleg bend on the stairs, she swore she saw a shadow pass across the grimy wall. She choked on whatever it was that was constricting her throat. Bile, fear… she didn’t know. Instinct told her to get out.

Darting back down into the living room, she ran to the stuck window and raised the poker above her head. She screwed up her eyes and brought it down on the glass over and over, smashing hard at the old panes. Adrenalin and fear fuelled her need to escape as shards of thin glass showered onto the quarry tiles. The brittle glazing bars didn’t take much force from the poker before there was a space big enough to climb through.

Shaking, she clambered up onto the ledge and coiled her legs out of the small gap. Remnants of glass cut into her shoulder, but she didn’t care. Whoever she’d heard up there was nearly down the stairs. She could hear slow, plodding footsteps on the wooden boards as if they didn’t have much urgency, as if they knew she was already terrified.

Claire jumped down off the windowsill onto the soil below. Her heel became trapped between two rocks, so she kicked off her shoes and ran, stumbling, panting, to the safety of her car. Her body didn’t feel like her own.

‘Oh God, oh God…’ She yanked the car door open and leapt inside, reaching for the ignition where she knew she’d left the keys. But they were gone.

‘No, no…!’ she cried, covering her face. She searched around frantically – in the ignition again, then on the floor and under the seat. She twisted around to check the back seat, the passenger side footwell…

The keys were gone. And so were her mobile phone and handbag.