I follow her gaze, and the air is punched from my lungs. A creature prowls opposite us, half hidden by the optic. It’s tall, maybe twice the height of me, and walks on two legs, the top of its body leaning forward at an odd angle. Only it’s not a thing of flesh and blood. It’s made of shadow: a swirling mass of black smoky air, its outline blurred and wispy.

I hold still, praying it doesn’t see me, when a movement catches my attention. Looking closely at the optic, I see that the glass is smashed, leaving a gaping hole down one side. A shadowy creature emerges from it and enters the room. This one is short and squat and jumps like a toad; its legs fat and its back mottled with diseased-looking skin.

A rumble sounds and a different creature emerges, its clawed hand appearing first and then a long snout. A forked tongue flicks from its mouth as it climbs out.

My mum shouts, ‘Quickly – to me!’

With the tip of a knife she draws an outline of a rectangle in the air. I run over and she pulls me next to her and then closes the invisible door. The creatures grunt and sniff as if they can tell we’re here but can’t see us.

My breath comes hard and fast. ‘What are those things?’

Another rumble builds and the red light glows brighter, the air pulsating around it. Arms and shoulders writhe and creatures pull themselves through the hole in the glass, twisting and snarling. More and more of the things emerge. Some swish long scaly tails, some crawl on eight legs, and others flap torn and tattered wings – hideous, impossible things made of darkness and hunger.

She shakes her head. ‘This wasn’t meant to happen. They weren’t meant to come through!’

‘Can you make them go?’

‘I don’t know. I need to get closer to the portal.’

Shielding her eyes, she peers at the optic. No creatures are emerging from it now. Instead, there’s a hazy image of a man with a long beard inside it. He glares into the room, his black eyes blazing, and every muscle in my body tenses. Corruption seeps out from him, washing over me in waves, and my stomach shrinks inside me.

Before I can ask if my mum sees him too, she turns away from me and raises the knife. I grab her arm and pull it down. ‘What are you doing? I thought you’d cast a circle to protect us.’

Her eyes fill with tenderness. ‘I’m sorry. I wish there was more time.’ She pulls me close and holds me tightly, as if she’s trying to make up for a thousand missed embraces, and I hug her back. It feels so good to be held by her, I don’t want to let go. She pulls away from me and clutches my shoulder.