Actually very fertile seeing as we’ve had one already, I think with grim amusement. She has her back to me whilst she takes off her coat and hangs it on one of the hooks near the front door, so I don’t need to hide my reaction. “God, it’s Baltic in here. Is the heating not working properly?” Carrie asks.

“It should be. It was fine earlier.” She’s right, though: the chill I’m feeling isn’t just the remnants of the cold outside. I’ve only been gone—what?—twenty-five minutes or so; surely the temperature inside couldn’t have dropped this much so quickly? I glance at my watch and try to recall the heating timing pattern, then put a hand to the hall radiator. It still holds some warmth, but it doesn’t seem as hot as I think it ought, given that the central heating should still be on. “I’ll go check.”

“I’ll put the kettle on,” Carrie calls after me.

The second floor, lit by the landing light that I must have indeed left on, is even colder. It’s not hard to trace the culprit: the bottom half of the wide sash window in the bathroom that I’ve been using is a couple of inches open. Was it open this morning? I haven’t ever opened it myself, and I can’t believe it was left ajar all the time the Manse was unoccupied. Surely I would have felt a draft whilst I showered if it had been open then? The boiler is in a cupboard in the same bathroom. There’s no light on it anywhere that I can see. I look in vain for instructions then tentatively press a button with a flame on it. There’s an encouraging whoof noise, then a blue pilot flame obligingly appears in a tiny open window in the metal casing.

Coming out of the bathroom, I’m faced with Carrie’s open bedroom door. That, at least, I’m sure has been open all day, offering a framed glimpse of the glorious view that lies beyond the wide bay windows. But now there is nothing beyond except a heavy pressing darkness. I have the uneasy sensation that mere glass can’t possibly keep it out, that the darkness will find cracks to ooze through, an inexorable creeping blanket of dark absorption that will eventually snuff out all light.