‘Shouldn’t have done that,’ says Peg, fluttering before me, his red wings a blur.

‘It was on our side . . .’ I say, savouring the sharp tang of the berry.

‘The roots aren’t. You’ll be corrupted.’

‘I’ll be fine.’

Peg sniffs. He’s an imp, and his favourite form is a small red bird with a golden beak. Whatever guise he’s in, he’s very beautiful, very vocal, and regularly very annoying. He’s a real stickler for the rules.

He’d be horrified at what I did earlier.

Because I really did it. A shiver of apprehension runs up my spine just at the thought of how I’ve disobeyed Nan. Peg peers around at me.

‘What was that? Are you poisoned?’

‘No! I was just thinking about something.’

‘Dark thoughts, ominous tidings – it’s the berry!’

‘It’s not the flipping berry! Now go and see what you can find out there . . .’

Peg is Nan’s familiar, and nowadays our watch imp; he scouts out the forest for trouble. I mean, there’s always trouble, but he’ll find out if anything’s about to start trouble here. There’s a magical boundary, just at the point where our fence divides the garden from the green marshland that leads to Winterspell, and the creatures in the forest don’t cross it, but sometimes I hear them at night, faint whispers of parties, the clamour of hooves, the high-pitched call of fierce, flying things. I’ve never managed to actually see them from so far away, no matter how many nights I’ve spent curled up on the cold windowsill, watching.

Our family ruled them all, long ago. We were the kings and queens of fae. But the Plaga came when I was two and killed my mother within a day. And my father was lost too – to illness, and to grief. With her dying breath, my mother called Nan back to the world of the living and charged her with bringing me up, safe and well. Nan saw the danger in the forest, and so we fled, and here we are, hiding from the forest, while the Shadow King’s legions grow stronger, day by day, fighting with the fae over the fate of Winterspell. We keep to our house, with all our books and wards and spells that apparently protect the rest of the human world from his creeping shadow magic.

When I was small, we ventured into the forest – under Nan’s glamour so that none of those creatures could sense us – and we searched for the palace, which is the heart of the Shadow King’s power. But we never found it. His darkness has warped the land, made it impossible to find even for us. And every time we went in there, the shadows were harder to hide from; they gathered thick about us, and the fae who fought them had to fight all the harder on those days. So we left. I could see how it upset Nan, to walk away from Winterspell and all the fae, but we only made it worse for them. We couldn’t go very far – her power, the thing that keeps her with me, is tied to the magic in the forest. So we have spent all these years hiding between the forest and the town. Nan used the last of her real magic to glamour the whole house, and us inside it – when I look in the mirror, I am human.