The scream came from Primrose Cottage, and Rosamund flings open her front door and almost falls through it, gripping the doorframe and bending over as though trying to catch her breath. ‘Elise!’ she cries. ‘Elise!’

As if a fire alarm has gone off, Dad appears through the darkness, hurrying towards Rosamund, and Finn races from the other direction.

I make my way towards Rosamund, and startle at the sight of the snowman Elise and Rosamund had so lovingly built that morning destroyed – broken, scattered. By the time I reach the cottage, Finn has taken Rosamund in his arms, and she’s sobbing into his chest, and he’s asking her what’s wrong.

‘What is it?’ yells Dad, reaching them. ‘What’s happened?’

Rosamund lifts her head, her face streaming with tears. ‘She’s gone!’ She pauses briefly. ‘Like last time. Like Lark. Elise has disappeared. And there’s so much blood.’ She gasps, as though her words have punctured her heart, before turning and racing back into the cottage.

We follow, and my eyes scan the room, falling on a Monopoly board, before moving on to Rosamund’s red, tearful face.

She takes a deep breath. ‘I left Elise reading in her room. I wanted to photograph the ruins. I asked her to come, but she wouldn’t. Oh God, why didn’t she come with me?’ She swallows, wipes tears from her cheeks. ‘I shouldn’t have left her on her own. Not after the message.’

‘Message?’

She pulls her phone from her pocket, fumbles shaking fingers across the screen. ‘Here,’ she says, passing it to me. I read the words:

Why bring your stepdaughter to Drummondale House? You know what happened to Lark.

‘Oh my God. Do you know who sent it?’ I say, passing her phone back to her, and she takes it with shaking hands.

‘I’ve no idea. It’s from an unknown sender.’

‘You mentioned blood?’ Finn says.

‘Yes. Upstairs in the shower room.’

He turns and bolts up the stairs two at a time. I follow, to see him crouched in front of a pool of congealing blood on the shower-room floor. He looks up at me. ‘Christ. What the hell’s happened here?’

I turn to see Rosamund and Dad behind me. ‘Call the police,’ I say, my voice quivering. ‘And an ambulance – Elise must be hurt somewhere.’ But I’m doubtful she’s even alive. Anyone losing this amount of blood …

Dad takes out his phone, and looks at the screen. ‘No signal … I’ll try outside.’ He descends the stairs, as though he’s glad to escape. Within moments the front door slams, and he’s gone.

Elise’s bedroom door stands open. It’s in darkness, but the landing light allows me to pick out the double bed, the ruffled quilt, and a book open like a butterfly on her bedside unit. Floor-length curtains are pulled closed across the window. Her pink holdall is propped against the wall.