Something made me extend my hand towards the window’s dirty exterior. I saw my fingers shake. Kirsten gripped my shoulder, as if to pull me back, then let go abruptly. The distance between my fingertips and the window closed with agonising slowness.

When I was younger I received an electric shock from our television; this was exactly the same. My body jumped and I pulled my hand away, its tendons taut. Andrew jumped as if in sympathy. My fingers tingled with the aftershock. Their tips were dirty with brown muck.

Kirsten was frozen, staring at the window. “It’s gone,” she hissed, “it’s gone back further into the house.”

The door didn’t seem like such a good idea under the circumstances. There might be another way in around the back.