I left the window open, and a shallow breeze stirs the curtains. I’m not sure, but I think the sound I heard is coming from outside. It’s faint and then it’s gone. I lean on the windowsill to look down at the swimming pool, and something sharp digs into my palm. I wince; embedded in the heel of my hand is a human tooth. It’s so tiny it can’t be an adult’s: sharply pointed, it’s a dull ivory, with a hollow where it once grew in a child’s jaw. A canine. I shudder. Whose is it and why is it on my bedroom windowsill? It must be Lotte’s or Theo’s – but even I know how much a tooth is worth to a child. Neither of them would have left it here.

I look out again. I can only see the dark expanse of water below me; the outline of the hill and the roof of the farmhouse where Carlo and his family live. I quietly pull on my jeans and T-shirt, slide my feet into flip-flops. I put the tooth in my pocket; it seems wrong to throw it in the bin. I listen at my father’s door, but he’s snoring. Bethany probably dosed him up with sleeping pills again. The wooden floorboards creak beneath my feet as I walk along the landing and squeak down the stairs.

The living room is empty. I open the back door – somebody has left it unlocked – and step outside. There’s the dull thrum of insects from the brush, but I can’t hear anything else and I wonder if I imagined it. Although the moon isn’t visible, there are so many stars it’s possible to make out the shape of the sun-loungers and the tables grouped around the pool; the water lapping at the stone sides, the Milky Way refracted on its surface. It’s beautiful. The faint stir of the wind is refreshing. I walk a couple of paces towards the pool. I’m wide awake now, all my senses tingling and alive, adrenaline fizzing through my veins. I don’t think there is anyone here, and I imagine the feel of that cool water against my skin. I’m about to peel off my jeans and dive into the inky depths when I notice something floating on the surface, gently bumping against the edge. I reach down and grab it. The water is colder than I expected. As I lift the object out, I realize it’s one of Lotte’s floats. In the starlight I can just about read the writing on the front. It says: Warning: will not protect against drowning. I shudder and drop it on a sun-lounger. I’m just about to go inside when I hear the noise again.