A cold wind gusts out of the night and whistles along the battlements of Castle Silverhill. It spatters icy raindrops against the leaded windows and sets them rattling in their casements. Tentacles of grey mist ooze from the moat and drift around the keep, probing the ancient stones for cracks and crevices, openings it can slink through to chill the hearts of those inside.

A movement catches my eye and I turn my attention to the painting I acquired decades ago, a work crafted in oils depicting the entrance to the dungeons.

The brushstrokes move, showing the heavy door to the cells opening and a person of a rather unsavoury nature emerging. Down there, along with the rats and a peculiar luminous fungus, a goblin called Grimmon has made his home.

You know how it is: you pop out to the shops for a loaf of bread and come home to find a goblin has moved into your cellar. Only, in my case, my cellar is less a single, dank room and more a warren of underground chambers, which I like to refer to as the dungeons. A vein on Grimmon’s temple throbs and he clenches his jaw whenever I call them that. He says it makes him sound like a criminal. Well, he might be for all I know.

The view in the painting moves as Grimmon, a great leather-bound volume tucked under his arm, walks to the steps. He wipes the slime from his feet on a mat, not because I asked him to – he’s quick to tell me – but because he doesn’t want to expose the sentient slime to my unwholesome personage. With clean feet he trudges up the seven flights of stone steps to the floor where a dim corridor, ill lit by guttering torches, leads to the studio where I toil. I’m hunched over a board embossed with letters of the alphabet. A glowing flat rectangle of crystal, filled with words, floats before me.

The goblin enters and brushes the wispy hairs of his forelock out of his eyes.

“It is done,” he says. His gaze strays to the painting. But he’s too late. It reverted to a still life of a dead mouse and a wedge of mouldy cheese the moment he entered my studio.

“All of it? The curly bits in the corners too?” I say.

“Yes.”

“Yes, what?”

Grimmon frowns. “Yes, I’m finished.”

“No.” I wag a finger at him. “I thought I told you to address me as Your Magnificence.”

“I didn’t think you were being serious. I mean, what kind of conceited idiot calls himself that?”

He’s nettled me, but I conceal it with a huff which I hope he’ll interpret as me brushing his insult aside because he’s not important enough for me to be concerned about what he thinks.

It’s stalemate and for the space of half a dozen heartbeats we stare at one another.

“Look, do you want to see it or not?” he says at last.

“Oh… um, yes. Please.”

He thumps the book down on my desk and opens it at the page he’s been working on.

And here it is: