It takes me less than three minutes to hack through the flesh and tendons of my left hand and sever my little and ring fingers and two knuckles. The pain is indescribable, as if I’m vaporising my hand with a white-hot laser, but I’m driven by the momentum of a strange euphoria: I am not going to let my son die in this place. I don’t black out, or lose consciousness, or shed a tear. It’s almost like childbirth: my pain means my son gets a chance to live.

As soon as it’s done, I wrench myself free from the handcuff and tug off my running hoodie, wrapping it around my mutilated hand to staunch the bleeding. I can’t let myself pass out, or I’ll bleed to death before I ever regain consciousness and this will all have been for nothing.

I wrench open the chest freezer with my good hand. Stacey didn’t lie: Peter is curled up on the bottom. He isn’t moving, and when I lean inside and put my index and middle fingers to his carotid artery, I can’t find a pulse. His skin is white, his lips blue, his hair frosted with ice. I don’t know if he’s alive. I don’t know how I’m going to get him out on my own.

I climb into the freezer with him. Blood from my mangled hand spatters across the sides of the freezer as I fumble my baby into my arms. I’m shivering uncontrollably in the cramped space, though I don’t know if it’s from shock or the cold or a combination of both.

Somehow I haul him onto my lap. He’s dead weight, slumped lifelessly against my chest. I still can’t tell if he’s breathing: the cold will have slowed his respiration so much it’ll be hard to detect even if he is alive. The adrenaline that has got me this far is suddenly ebbing, and I don’t think I have the strength to get myself out of the freezer, never mind my son.

And then I feel it: his heartbeat.

Slow, but steady.

I am not going to let my son die in this place.

With a sudden renewed burst of energy, I heave Peter up to the lip of the freezer, bracing myself beneath him as I take his weight. It costs every ounce of strength I have left to lower him onto the concrete floor without dropping him. I clamber out and collapse beside him, enveloping his body with mine to warm him.

‘Sweetheart, come on,’ I plead, chafing his arms with mine. ‘Wake up, Peter. You need to wake up.’