‘In the fjord. Derry went swimming, too.’

None of it made any sense, but I could see Gaia was growing frustrated so I changed the subject. ‘All right, my lovely,’ I said in my finest Mary Poppins voice. ‘Enough about bad dreams. That’s what your worry doll is for, OK? She absorbs all your bad thoughts and fears like a sponge, leaving you to dream sweet …’

‘I did see Mumma,’ she said in a firm voice, way older than her six and a half years. She held me in a fixed stare for a handful of seconds, before turning over and laying her head on the pillow.

I placed a hand on her shoulder. ‘Goodnight,’ I said. Usually she’d reply, but tonight she didn’t. And I felt guilty.

I went to my room and waited for Gaia to come creeping in, but she didn’t. I flipped open my laptop and tried to add to my story, but the protagonist, Alexa, stood in the proscenium of my mind’s eye, her face pulled into a tight sulk and her arms folded. One foot tapping. You should have let Gaia speak.

I sat watching the rain for a long time, feeling rather blue and surprisingly lonely. My own memories were starting to dredge up like rusty shipwrecks inhabited by sharks and killer squid. I got up and headed to the kitchen, intent on fixing Coco a bottle of milk for the inevitable midnight cry of ‘Ya-ya!’

But on returning to bed, bottle of milk in hand, I heard a noise. A moan, or a sort of low cry. At first I thought it was Coco, bang on schedule, demanding her milk.

I walked quickly along the hallway to the stairs. The door at the end of the hall was ajar. I knew the inside of the house intimately, from the yellowing skirting boards to which floorboards creaked and where gangs of spiders liked to hang out, and I happened to know for a fact that this door was always locked. Fiercely, unremittingly locked. The door led to The Basement, that unspoken hinterland into which I was forbidden to venture. But now it was open.

A chilly breeze washed over me, a breeze that was belching from the depths of the basement. A sour odour permeated the air. My mind spun to the cause of such a weird smell. A torture chamber. Or a vat of chemicals for storing dead bodies. Stop it, I told my brain. It’s probably just used for storage, like every normal cellar. Maybe someone’s giving the place a clean. That’ll be the reason for the smell, not formaldehyde or decomposing corpses.

Maren or Tom would be down there, scrubbing their completely-innocent, corpse-free basement with eco-friendly liquids. But just then, another sound came from the basement, and immediately two thoughts laced together: Gaia had risen from her bed and followed me. And she had gone down into the basement.