Tom grabs our things and turns to David. ‘Aren’t you coming up with us?’

‘No, I’ll get off. I’ve already delivered Sarah’s supplies for winter and I don’t want to turn up unexpected.’ He straightens his back and I get the sense he’s steeling himself to leave us. ‘She’s never had visitors before; you must be very special to her. Give her my best, won’t you?’

I smile politely, surprised by his sudden formality. ‘Well, thanks for everything. It was kind of you to bring us.’ I raise my hand in farewell then yank up my shorts and march along the path.

The quad bike starts up and Tom stands and watches it drive away.

‘You coming?’ I call.

He hurries to catch up with me. ‘It seems a bit weird, dropping us here. I mean, what if your mum’s out?’

‘I hardly think she’s popped to Tesco, do you?’

‘No, but I thought the plan was for her to talk to David, and persuade him to let you stay on your own.’

I shrug, not knowing whether she’s going to let me stay the night, never mind both of us. ‘Don’t worry. I’m sure David will take you back with him tomorrow.’

Tom nods, but his eyes are full of uncertainty. I’m not sure whether he’s worried about being stranded on the island, or how my mother will react when she has unexpected visitors. Either way, I’m glad I warned him that she doesn’t want me here.

We make our way along the track without speaking, the wail of the wind and the crashing waves the only sounds. A faint early-evening moon hangs high in the sky, its silvery face shrouded by cloud. I glance at it and shiver. If my mum doesn’t let us stay, we’ll have a long walk back to the farmhouse – in the dark.

A red light appears, bathing the gravel before us, and we lift our chins and look up. The glow is coming from the top of the lighthouse.

Tom mutters. ‘I thought lighthouses had a white light?’

‘Me too.’

The light doesn’t sweep across the land. It remains fixed, stretching for miles in all directions, spilling over the earth like blood. The tower seemed so majestic from a distance, but close up it looks different – a tyrannical, monstrous thing.

We pass several disused-looking properties and Tom stops to peer inside the window of a circular stone building with a flat roof, its white-painted walls badly peeling. I look inside and see a bed in the centre of the room, surrounded by bits of broken furniture.

Next to it is the lighthouse. Adjoining the square tower is a low connecting building, no more than six feet long, with a dark green door in the middle. At the other end is a cottage with a row of square windows on the ground floor and two large dormer ones in the slate roof. We walk to the end of the cottage and find another green door.