‘I’ll run. I’ll run as fast as I can to Knackers Yard and call the hospital. I know the way. I know the numbers to press. I’ll be really quick and—’

Tears filled her eyes. She looked up at the sky. I followed her gaze; dark clouds that looked like bruises crowded the very top. Below them sat an orangey-pink colour; a shade so delicate and unusual I couldn’t tear my eyes away. The sun was hidden behind the dark clouds as if scared to come out.

‘What if she comes back and you’re not here to help me?’ Olivia said. ‘I’m too weak to run. I can’t fight her, not in this state. Please. We have to go inside and find her keys. We have to do it now.’

I thought about Mother hurting Olivia, maybe even killing her like she’d killed Patrick and Derek, and my gut churned. A cold sweat broke out over every inch of my skin, but I nodded and helped Olivia up the small step into the kitchen.

As soon as my foot touched the floor, gloom seeped into my mouth, down my throat and deep inside my heart, making it race so fast I thought I was going to pass out.

Sensing my fear, Olivia held my arm and I clung onto her fragile frame. She murmured reassuring things and my feet moved, and then I was guiding her through the room as quickly as possible, somehow managing to stay upright, my gaze locked on the ground, my breathing shallow and fast.

Focusing on my feet, I hurried her down the hallway. We reached the foot of the stairs and Olivia used the banister and my support to drag herself up each step, her grunts of pain and the creaking floorboards creating an unsettling melody that made me shiver.

On the landing, I flicked on the light and led her to Mother’s bedroom. Out of the three rooms where she might be keeping a spare car key, I thought her bedroom was the most likely. She nearly always kept it locked. It might have been to stop me from seeing her crazy doll display, but it also might have been to stop me from finding any other keys. Or something else too horrible to name.

To my surprise, her bedroom was unlocked. I realized she’d probably stopped bothering to lock it when she moved me into the hole in the back garden.

I tried Emma’s old room and that too was unlocked.

‘I can kneel on the floor and search through drawers and behind things,’ Olivia said. ‘As long as I’m not standing, I think I’ll be able to help look for the key.’