She sits beside Gaia and strokes her forehead to calm her, but just then she stiffens.

‘What’s wrong, Mumma?’ Gaia murmurs when she feels her mother straighten, primed to get up.

Aurelia shushes her. Her instincts home in on the source of the sound. A low human voice, or perhaps the low growl of an animal. A bear, perhaps. She knows the sound came from the basement. This makes no sense. How could she possibly hear such a low sound from two levels down? And yet she did.

All the hairs on Aurelia’s arms stand on end.

‘Stay here,’ Aurelia whispers to her, rising to inspect the noise.

‘Where are you going, Mumma?’ Gaia says, swinging her legs over the side to follow her.

‘Stay here,’ Aurelia says again, in a voice that fixes Gaia to the bed. Seeing Gaia’s face she softens. ‘You stay in bed, sweetheart, OK?’

‘But why …?’

She sighs. ‘Look, I think I heard a noise downstairs. I’m just going to check it out, OK?’ She forces a smile, but Gaia recognizes that strained, false look immediately and her worry doubles in size. She wiggles back down under the covers and tries hard not to cry.

Aurelia heads downstairs. No sign of Maren anywhere. She likes to take a walk once a day. She must be out. She pats the pocket of her cardigan to ensure her mobile phone is at hand. Before she reaches the bottom stair she takes the phone out to check she’s got a signal – yes – then freezes as she hears the sound again.

Aurelia.

A voice. It said her name.

It came from the basement.

Quickly she taps her phone and calls Tom. He can’t do anything from where he is, at least not physically, but if it’s an intruder she wants him to know about it. No answer. Damn him. He never answers his phone when there’s a genuine emergency – she thinks back ruefully to when she was in labour with Coco – but mysteriously manages to answer clients, cold callers, and wrong numbers on first ring.

She wraps her fingers around the handle of the basement door. Her heart is pounding furiously. Upstairs she can hear the drumming of little feet along creaking floorboards. Gaia, terrified for her mother and straining to listen out for her.

She opens the door as quietly as she can. A blast of cold, damp air. She holds her breath and leans into the stillness. No sound, yet her instincts are ringing like bells, telling her that someone – or something – is down there. And they are requesting her presence. She places a foot on to the first stair. The walls are raw stone, the darkness impenetrable.

She tries Tom’s number again, and while it rings she calls out ‘Hello?’