No. I think someone else wrote that note.

I remember her fingers in the post office, strong fingers, with blood under the nails.

And I am certain, in a way that I wasn’t with Luc, that she is capable of this.

When I get to the B&B I crawl into bed with Freya, and then we both fall into sleep like bodies sinking into deep water. I surface, hours later, and for a moment I have the strangest sense of disconnection.

The B&B is on the coast road, just a few miles up from the school, and the view from my room as I sit up, adjusting my dishevelled, salt-stained clothes and smoothing Freya’s sweaty hair away from her face, is exactly the same as the view from Tower 2B, all those years ago.

For a second, even though my daughter is asleep beside me, I am fifteen again and I am back there – the sound of the gulls in my ears, the strange clear light splashing across the wooden windowsill, my best friend in bed beside me.

I close my eyes, listening to the sound of the past, imagining myself back into the skin of the girl I once was, a girl whose friends were still around her, whose mistakes were ahead of her.

I am happy.

And then Freya stirs and squawks and the illusion is broken, and I am thirty-two and a lawyer and a mother again. And the knowledge in the back of my mind that I have been wrestling with all night comes down upon me like a weight.

Kate and Luc are dead.

I scoop Freya up and we make our way downstairs, yawning, to where Fatima and Thea are sitting in the sun porch overlooking the sea.

It is July, but the day is chilly and grey, and the clouds threaten rain, their dark streaks the exact shade of the grey fur that ripples along Shadow’s spine. He is curled at Thea’s feet, his black nose in her hand, but he looks up as I come in, his eyes bright for a moment, and then he sinks back. I know the person he was looking for. How do you explain the finality and unfairness of Kate’s death to a dog? I barely understand it myself.

‘We got a call from the police station,’ Fatima says. She draws her knees up in the chair, hugging them to herself. ‘They want us to come in at four this afternoon. We need to work out what to say.’

‘I know.’ I sigh and rub my eyes, and then put Freya down on the floor to play with some old magazines left there for guests to read. She tears at the cover of one with a little shriek, and I know I should stop her, but I am just too tired. I don’t care any more.

We sit for a long moment in silence, watching her, and I know without asking that the others have spent the night as I did: struggling to understand, struggling to believe what has happened. I feel as if yesterday I had four limbs, and today I have woken with only three.

‘She broke the rules,’ Thea says. Her voice is low, bewildered. ‘She lied to us. She lied to us. If only she’d told us. Didn’t she trust us?’

‘It wasn’t her secret to tell,’ I say. I am thinking not just of Kate, but of Owen. Of the way I have lied to him all these years, betraying our own unwritten rules. Because there is no right answer, is there? Just a trade – one betrayal for another. Kate had the choice of protecting Luc’s secret, or lying to her friends. And she chose to lie. She chose to break the rules. She chose … I swallow at the realisation. She chose to protect Luc. But she chose, too, to protect us.

‘I just don’t get it,’ Fatima bursts out. Her fists on the chintz cover of the armchair are clenched. ‘I don’t get why Ambrose let it happen! An oral overdose takes time, and even if he didn’t realise what was happening straight away, he clearly knew what was happening in time to write that note. He could have dialled 999! Why the hell did he spend his last moments telling Kate to save Luc, instead of trying to save himself?’

‘Maybe he didn’t have a choice,’ Thea says. She shifts in her chair, pulls the cuffs of her woollen sweater down over her ragged fingers. ‘There’s no landline at the Mill, remember? I don’t even know if Ambrose had a mobile in those days. Kate did, but I never saw him with one.’

‘Or maybe …’ I stop. I look down at Freya, playing on the rug.

‘What?’ Thea demands.

‘Maybe saving himself wasn’t the most important thing to him.’ There is no answer to that. Fatima only bites her lip, and Thea looks away, out of the window towards the restless sea. I wonder if she is thinking of her own father, and asking herself whether he would have made the same choice. Somehow I doubt it.

I think of Mary Wren, of her words at the level crossing. He would have walked through fire for those kids …

And then I remember something else she said, and my stomach shifts.

‘There’s something I need to tell you,’ I say. Thea looks up.

‘You were asking in the car, about the sheep, and I couldn’t tell you then, but –’ I stop, trying to marshal my thoughts, trying to explain the conviction that has been spreading like a shadow across my mind since that lift to the station. ‘We thought it was Luc because it fitted with what we knew, but I think we were wrong. He had as much to lose as us, with the truth coming out. More. And anyway, I’m fairly sure he was in custody that night in Rye.’ They don’t ask me to explain, and I don’t volunteer to. ‘And there’s something else – something Kate told me when I came down without you both.’

‘Spit it out,’ Thea says gruffly.

‘She was being blackmailed,’ I say flatly. ‘It had been going on for years. That’s what the sheep was about, and the drawings. It was a way of suggesting that she start bleeding us too.’

‘No!’ Fatima says. Her face is pale against the dark headscarf. ‘No! How could she not tell us?’

‘She didn’t want us to worry,’ I say helplessly. It seems so futile now. How I wish she had told us. ‘But it just doesn’t seem like something Luc would do – and besides, it started years back, while he was still in France.’

‘Then who?’ Thea demands.

‘Mary Wren.’

There is a long silence. For a minute they both just sit, and then, slowly, Fatima nods.

‘She’s always hated Kate.’

‘But where’s this come from?’ Thea asks. Her fingers move restlessly in Shadow’s fur, smoothing his ears, the smoke-coloured hairs catching on her rough, bitten skin.

‘It was on the way to the station,’ I say. I press my fingers to my forehead, trying to remember her words. My head is aching and Freya’s joyous shrieks as she shreds the magazine are making it worse. ‘Mary gave me a lift, and she said something … I didn’t pay attention at the time, I was too shocked about what she’d said about Kate and Luc … but she said something about Kate and the sheep, she said she’s got blood on her hands, and not just sheep’s blood either. But how would she know about the sheep?’

‘Mark?’ Fatima guesses, but Thea shakes her head.

‘Kate didn’t call the police, remember? Though I guess the farmer could have called it in.’

‘He could,’ I say. ‘But I’m pretty sure Kate paid him to keep quiet. That was the point of the two hundred pounds. But it’s not just what Mary said, it – it was the way she said it. It was –’ I break off, struggling to find the words to explain. ‘It was … personal. Gloating. Like she was pleased Kate’s chickens were coming home to roost. That note, it was venomous, do you know what I mean? It reeked of hate, and I got the same feeling from Mary when she said those words. She wrote that note, I’m sure she did. And I think she sent the pictures too. She’s the only person who could have got hold of all our addresses.’

‘So what do we do?’ Fatima asks.

Thea shrugs.

‘Do? What can we do? Nothing. We say nothing. We can’t tell Mark, can we?’

‘So we just let it go? We let her threaten us and get away with it?’

‘We keep lying,’ Thea says grimly. ‘Only this time, we get it right. We sort out a story and we stick to it, and we tell it to everyone. To the police, to our families – everyone. We’ve got to get them to believe that Ambrose committed suicide, it’s what he wanted after all. It’s what Kate wanted. But I just wish we had something to back up our story.’