When I was younger I could easily stand up in the largest chamber, but now I have to bend almost double. I peer inside and the back of my neck prickles. There’s a black hole three times the size of a rabbit hole, the wood around it scored as if someone has cut it with a knife. I blink against the gloom, unable to believe what I’m seeing. Blackness emanates from it, growing bigger and then smaller. A dark, pulsating heart.

Buzzing fills the air, like a swarm of flies or the rush of water but higher pitched – the sound of an electrical current almost. A stench of decay sends a wave of revulsion through my stomach. It feels like we’ve stumbled across a decomposing body covered in rotten leaves. We shouldn’t be here. I want to move, but I can’t.

A loud bark breaks the spell. Gandalf is on the porch, growling ferociously as if we are the ones who need saving. He jumps in circles, barking madly. Warning us to run.

7

I slam the door and drag the bolt across. Stig is doubled over, palms on his knees, panting hard. Droplets of water cling to his hair and clothes ‘You OK?’ he asks. I shake my head, unable to speak. ‘You’re fast! I couldn’t keep up,’ he laughs.

My lips twitch upward but I don’t feel like smiling. There’s something wrong with that tree. Unnatural. I inhale deeply through my nose but my stomach won’t stop churning. Just the memory of that putrid smell makes me want to heave. The hole can’t have been there when I came last summer, I would have noticed. It seemed too big to have been dug by an animal, yet the grooves in the wood looked like claw marks.

Stig peers out the window. ‘The fog is right on top of us!’ He wipes his breath from the glass and gestures for me to look. The world outside is gone, replaced by a dense uniform grey. Mist swirls over the porch, wrapping itself around the balustrades like a scarf looking for a neck to strangle. The room darkens as fog drifts across the window, devouring us whole. The cabin is freezing, colder than I’ve ever known. I look at the stove, expecting to see a pile of ash, but the embers glow orange.

‘Did you notice anything funny – I mean, odd? Just now, outside?’

Stig shushes the dog, who growls at the door as if Death itself were standing on the porch. ‘You mean Gandalf? Dogs can be affected by the weather. He’ll be fine.’