If all of that is true, then what happens now? I literally cannot move, and Celia and Malcolm keep darting glances over towards me. I think whatever it was that Celia injected me with is not a mild sedative. It’s something far worse. My insides turn to water as I realise that Celia is not in fact my friend. She’s not the wonderful mother-in-law I made her out to be. She’s not on my side at all and never has been. I think she’s been keeping me close all these years so she could keep an eye on me after what happened with Toby and Dina. I can’t stop thinking about the look she gave me when she tried to stop me calling the police all those years ago. When she shoved me backwards. It was vicious and triumphant.

Does Toby know his mother is here? Has he given her his blessing for whatever is going on right now? Oh, dear Lord, what if Celia plans to do away with me? What if I never see Alice and Jamie again and they’re left to be raised by their murdering father and psychopathic grandparents? I have to get out of this. I have to save my children.

A knock at the door brings me back to my present surroundings. Please let it be someone good. Someone I can trust to help me.

‘Zoe! You in there?’

Thank goodness! It’s my dad! He goes quiet for a moment, no doubt waiting for my reply. I pray for him not to leave, to somehow open the door and rescue me. If only I could call out to him. I’m sending messages from my brain to my vocal chords, but nothing’s happening. I can’t so much as force out a whisper.

Celia looks at Malcolm and puts a finger to her lips. He nods. Their actions confirm that I’m in terrible danger.

Dad calls out once more, and I cling on to the sound of his voice. ‘I tried to find the others but they’re not in their rooms. I’m worried about you, love. If you can hear me, open the door!’ He knocks harder this time and tries the handle. I hear it clicking up and down. But of course the door is locked. No one is going to be able to open it.

If only he’d come by earlier, before Celia had injected me with whatever it was. Please find a way to open the door. Kick it down. Yell! Call for help. Please.

‘Zoe?’ Silence. ‘Ah, all right. You sleep well. I’ll see you tomorrow.’

No, please, no. Come back!

Celia and Malcolm remain still and quiet until Dad’s footsteps have receded. They’re hunched together on the bed with Malcolm’s rucksack between them, like a couple of huge spiders crouched over their prey.