‘Should I give it to Mark Wren?’ Kate asks huskily. ‘I mean it might stop this whole thing. It answers so many questions …’

But it raises so many more. Like, why didn’t Kate go to the police with this note seventeen years ago?

‘What would you say?’ I ask at last. ‘About where you found it? How would you explain it?’

‘I don’t know. I could say I found it that night, but I didn’t tell anyone – I could say the truth, basically, that Dad was gone, that I was afraid of losing the house. But I don’t have to involve the rest of you – the burial, everything else, I could leave that out. Or I could say that I only found it later, months afterwards.’

‘God, Kate, I don’t know.’ I scrub my fists into my eyes, trying to chase away the remnants of bleary-eyed exhaustion that seem to be stopping me from thinking properly. Behind my lids, lights spark and dark flowers bloom. ‘All those stories, they seem to be asking more questions than they answer, and besides –’

And then I stop.

‘Besides what?’ Kate says, and there’s a note in her voice I can’t quite read. Defensiveness? Fear?

Shit. I did not mean to go down this route. But I can’t think what else to say. Rule Four of the Lying Game – we don’t lie to each other, right?

‘Besides … if you give them that note they’ll want to verify it.’

‘What do you mean?’

‘Kate, I have to ask this.’ I swallow, trying to think of a way to phrase it that doesn’t sound like I am thinking what I’m thinking. ‘Please understand, whatever you say, whatever happened, I won’t judge you. I just have to know – you owe us that, right?’

‘Isa, you’re scaring me,’ Kate says flatly, but there’s something in her eyes I don’t like, something worried and evasive.

‘That note. It – it doesn’t add up. You know it doesn’t. Ambrose committed suicide because of the drawings, that’s what we always thought, right?’

Kate nods, but slowly, like she’s wary of where I am going.

‘But the timings are all wrong – the drawings didn’t turn up at school until after he died.’ I swallow again. I think of Kate’s facility for forgery, for the paintings she faked for years after Ambrose’s death. I think of the blackmail demands she has been paying for more than fifteen years, rather than go to the police with this note – demands she has concealed from us, though we had a right to know. ‘Kate, I guess what I’m asking is … did Ambrose definitely write that note?’

‘He wrote that note,’ she says, and her face is hard.

‘But it doesn’t make sense. And look, he took a heroin overdose, right? That’s what we’ve always thought. But then why were his works all neatly packed up in the tin? Wouldn’t he have just shot up and dropped them beside his chair?’

‘He wrote that note,’ Kate repeats doggedly. ‘If anyone should know, I should.’

‘It’s just –’ I stop. I can’t think how to say this, say what I’m thinking. Kate squares her shoulders, pulls her dressing gown around herself.

‘What are you asking, Isa? Are you asking if I killed my own father?’

There is silence.

The words are shocking, spoken aloud like that – my vague, amorphous suspicions given concrete shape and edges hard enough to wound.

‘I don’t know,’ I say at last. My voice is croaky. ‘I’m asking … I’m asking if there’s something else we should know before we go into that police interview.’

‘There is nothing else you need to know.’ Her voice is stony.

‘There’s nothing else we need to know, or there’s nothing else full stop?’

‘There’s nothing else you need to know.’

‘So there is something else? You’re just not telling me what?’

‘For fuck’s sake, please stop asking me, Isa!’ Her face is anguished, and she paces to the window, Shadow feeling her distress and pacing with her. ‘There’s nothing else I can tell you – please, please believe me.’

‘Thea said –’ I start, and then feel my courage almost fail, but I have to ask it. I have to know. ‘Kate, Thea said Ambrose was sending you away. Is that true? Why? Why would he do that?’

For a minute Kate stares at me, frozen, her face white.

And then she makes a noise like a sob and turns away, snatching up her coat and slinging it on over her pyjamas, shoving her feet into the mud-spattered wellingtons that stand beside the doorway. She grabs Shadow’s lead, the dog anxiously following at her heels, its gaze turned up to Kate’s trying to understand her distress – and then she’s gone, the door slamming behind her.

The noise sounds like a gunshot, echoing in the rafters and making the cups on the dresser chink with indignation. Freya, playing happily on the rug at my feet, jumps at the noise, her small face crumpling with shock as she begins to wail.

I want to pursue Kate, pin her down for answers. But I can’t, I have to comfort my child.

I stand for a minute, irresolute, listening to the howling Freya, and the sound of Kate’s footsteps hurrying away across the bridge, and then with a growl of exasperation I pick Freya up and hurry to the window.

She is red-faced and kicking, full of a woe out of proportion to the sudden noise, and as I try to soothe her, I watch Kate’s retreating silhouette disappearing up the shoreline with Shadow. And I wonder.

I wonder about the words she chose.

There’s nothing else I can tell you.

Kate is a woman of few words – she always has been. So there must be a reason. A reason why she didn’t just say, There’s nothing else to tell.

And as I watch her, disappearing into the mist, I wonder what that reason is, and whether I’ve made a huge mistake by coming here.

WITH KATE AND Shadow both out, the house is strange and quiet, the sea mist spattering at the windows and the puddles from last night still drying on the dark, damp-stained boards.

In the mist, the Mill feels closer to the sea than ever, more like a decrepit, waterlogged boat run adrift on a bank than a building meant to be part of the land. The mist seems to have crept into the wooden boards and beams in the night, and the place is cold, the floorboards chilly with damp beneath my feet.

I feed Freya, and then, setting her back down to play on the floor with some paperweights, I light the wood-burning stove, watching as the salt-soaked driftwood flares blue and green behind the sooty glass, and then I curl on the sofa and try to think what to do.

It’s Luc I keep coming back to. Does he know more than he is letting on? He and Kate were so close, and now his love for her has turned to such bitterness. Why?

I press my hands to my face, remembering … the heat of his skin, the feeling of his limbs against mine … I feel suddenly like I am drowning.

It is late lunchtime when Kate comes back, but she shakes her head at the sandwiches I’m making, and takes Shadow up the stairs to her bedroom, and there’s a part of me that’s relieved. What I said, the suspicions I voiced, they were close to unforgivable, and I’m not sure if I can face her.

When I go up to put Freya down for her nap, I can hear her, pacing about on the floor above, even see her shape occasionally through the bare gappy boards as her silhouette passes across a window, blocking out the slivers of grey light that filter down through the cracks.

Freya is hard to get to sleep, but at last she’s slumbering, and I go back down to the living room to try to sit at the window, watching the restless waters of the Reach. It is not quite four o’clock, and the tide is almost at its height, an exceptionally high tide, one of the highest since we’ve been here. The jetty is awash, and when the wind blows off the Reach, water comes lapping in beneath the doors to the seaward side of the Mill.

The mist has lifted slightly, but the sky is still cloudy and chill, and it’s hard to remember the heat of just a few weeks ago as I sit, watching the iron-grey water slapping at the boards outside. Did we really swim in that estuary earlier this month? It seems impossible that it could be the same place as the warm, balmy water where we floated and swam and laughed. Everything has changed.