Hanna wasn’t on the deck as she stepped into the clearing, although a half-empty wine bottle and glass stood on the small table.

‘Hanna, it’s just me,’ she stage-whispered as she opened the door and walked into the open-plan space. There was no one on the sofas either, and the TV was off, but she could see her phone on the worktop, beside the fruit bowl. ‘I forgot my phone.’

She picked it up and waited a moment, expecting the sound of her boss’s barefooted steps on the wooden floor. With everything on one level in the cabin, noise travelled easily.

‘Hanna?’

Still nothing. Was she in the bathroom?

With a shrug, she turned and left, closing the door softly behind her. She walked down to the beach, checking her phone for missed messages and calls. Just one from her hairdresser, putting back an appointment she had forgotten even booking. At the water’s edge, she slid off her shoes and held them in one hand, beginning to wade into the water, before stopping suddenly.

What?

She frowned, blinking once, twice, at the distant horizon. There was no boat blotting its perfect curve. She kept staring at it, trying to comprehend the situation. The boat wasn’t there. It clearly wasn’t there. But no one apart from her and Hanna had a set of keys.

With a gasp, she turned back to the cabin. The never-quite-setting sun reflected dazzlingly on the sliding glass doors, like the pink-tinted lenses of Ray-Ban aviators, mirroring the world back to itself.

Running, feeling the sand clump between her wet toes, she dashed up the beach and up the steps onto the deck. She was supposed to dunk her feet in the yellow water bucket by the door before she went in – it was a cardinal rule in the Mogerts’ summer house – but she ran straight through, oblivious to the sandy footprints marking a path behind her. She looked into the bathroom as she went past. Empty.

Hanna and Max’s bedroom.

Empty.

Heart clattering, she peered in to the children’s bedrooms too – but they were all sleeping soundly, skinny limbs thrown atop the covers in the heat.

Bell stood breathless in the hall, trying to make sense of what was going on, trying to find another explanation for what the facts were showing her. But there was only one truth. The boat was gone. Hanna was gone. And her children had been left alone in this cabin on an island.

Had there been an emergency? There must have been. And yet, if so, why hadn’t she told Bell and asked her to come back down here? To just . . . leave them here? Alone and vulnerable whilst they slept?

Bell felt an uneasy sensation swirling in the pit of her stomach, a small monster settling into a restless sleep. She walked back out onto the deck, scanning the dusky millpond water for signs of a small boat puttering back into view; but there was only that big, blushing, empty sky and the vast, unbroken stretch of sea.