Liam presses his fingernail to the glass. ‘It’s been done from the outside. With a knife or something sharp.’

I think about the sound I heard last night – of something scraping against glass – and feel a chill all over my body. ‘What should we do?’ I ask, looking to him for answers.

‘Let’s go back inside,’ he says.

I glance around. Is whoever did this watching us right now? I feel exposed, as naked as I was last night when someone – this same someone – spied on us through the window.

‘We’re meant to be on the island by ourselves,’ Liam rages, once we’re back inside and he’s shut and locked the door behind us. ‘We’re meant to have total privacy, and instead we’ve got some sicko pervert stalking us, watching us have sex.’

He puts his coffee down on the table and starts to pace the front room.

‘Maybe it was some kids from the mainland?’ I suggest tentatively, chewing on my thumbnail with worry. ‘Or maybe someone’s living on the island and they forgot to tell us.’

Liam stops pacing. ‘Where? Where would anyone be living? There’s no other houses!’

I shake my head and shrug. ‘I don’t know.’ But I think about the castle. Wouldn’t that be the obvious place for someone to be living – or squatting?

‘And why wouldn’t they have warned us? And who the hell sneaks up on a place at night and spies through the window?’ Liam mutters, marching back and forth in front of the fire.

‘Could it be a groundsman or something like that?’ I ask. ‘One of the cleaners perhaps?’

‘There is no groundsman. And anyway, if there was, why wouldn’t they come during the daytime?’ he argues. ‘They could knock on the door and say hello. Why lurk in the dark, spying on people? They could be arrested for this.’

I perch on the arm of the sofa and think about the person watching us last night. Was the same person following us in the forest earlier in the day? Or was I imagining that?

‘It could be a treasure hunter.’

‘What?’

Liam nods at the history book. I remember what he said about the monks burying treasure and our silly idea of going to look for it. ‘You think someone’s here on the island, trying to dig up buried gold?’ I ask.

Liam shrugs. ‘Why not? Maybe they’re trying to frighten us off the island so they can keep up their search.’

He starts pacing again, his fists clenching and unclenching with frustration. Then he stops abruptly and looks at me. ‘Didn’t the boatman mention a satellite phone? For emergencies?’

I nod.

Liam looks around the room. ‘I wonder where it is.’