Mary was not the only person who overheard Kate fighting with Ambrose. Luc must have heard them too, and he must have understood what Thea and I had not – that he was the one to be sent away, not Kate. I don’t know where – to boarding school most likely, from what Ambrose said to Thea. But Luc, betrayed too many times, must have jumped to the conclusion he had always feared. He thought Ambrose was sending him back to his mother.

And he did something utterly, utterly stupid – the act of a fifteen-year-old, painfully in love, and desperate not to be sent back to the hell he had escaped from.

Did he mean to kill Ambrose? I don’t know. As I sit there, my eyes locked on Freya’s cherubic, sleeping face, I wonder, and I can believe both scenarios. Perhaps he did want to kill Ambrose – a moment’s fury, bitterly regretted when it was too late to undo. Perhaps he just wanted to punish him, disgrace him. Or perhaps he wasn’t thinking at all – just acting out the anger and despair burning inside him.

I want to believe that it was all a mistake. That he never meant to kill, that he only wanted to humiliate Ambrose, to have him dial 999 and be found in a pool of heroin-tainted vomit, sacked from his job, suffering the way Luc was about to suffer in return. He was the child of an addict, who had grown up around heroin, and he must have known the unreliability of an oral overdose, the time it would take for Ambrose to die, the possibility of reversing the effects.

But I’m not certain.

In a way, it doesn’t really matter any more. What matters … what matters is what he did.

He did just as Kate had told us, in her strange, cold, step-by-step account of actions she was taking responsibility for. He bunked off school, making his way back to the Mill in the daytime when he was sure that Kate and Ambrose would both be at Salten House. There he poured Ambrose’s stash into a screw-top bottle of wine and left it on the table for him to find when he came home from school that evening, and then he gathered up the most incriminating drawings he could find, and sent them to the school.

Oh, Ambrose. I try to imagine his feelings when he realised what Luc had done. Was it the odd taste of the wine that alerted him? Or the strange sleepiness that began to steal over him? It would have taken time … time for Ambrose to notice what was happening … time to put two and two together as the heroin filtered through his stomach lining and into his blood.

I sit there, holding Freya’s hand, and in my mind’s eye, I see it all, unreeling like a sepia film. Ambrose examining the bottle, and then getting up, his feet unsteady. Walking to the dresser, where the tin was concealed. Opening it up … and realising then what Luc had done, and the size of the dose he had swallowed.

What did he think, what did he feel as his crabbed hands scratched out those wavering letters, begging Kate to protect her brother from the consequences of what he had done?

I don’t know. I can’t begin to imagine the pain of realising what had happened, the magnitude of the mistake that Luc had made, and the bitter impulsive revenge he had taken. But there is one thing I am sure of, as I look down at Freya, and feel her fingers tight on mine. For the first time, I understand Ambrose’s actions. I understand them completely, and it all makes sense at last.

His first thought was not to save himself, but to protect his child. The boy he had raised and loved and tried and failed to protect.

He had let Luc go back to that hell, the sweet trusting toddler he had saved from the Reach as a baby, and whose nappies he had changed, and whose mother he had loved, before she fell apart.

He had let Luc go once, and now he understood that from Luc’s perspective, he had been planning to betray him once again. I was foolish not to see where my actions would lead … I am doing this so that no one else will have to suffer …

He wrote that note to make sure that only one life would be forfeit – his own. And he wrote it to Kate, not Luc, knowing that she, who knew her father better than any other person in the world, would understand and know what he was saying – that he was asking her to protect her brother.

Don’t blame anyone else, my sweet. I have made my decision and I’m at peace with it … Above all, don’t let all this be in vain.

And Kate … Kate carried out her father’s wishes as best she could. She protected Luc, she lied for him, year, after year, after year. But one part of Ambrose’s letter she could not fulfil. She did blame Luc. She blamed him bitterly, for what he had done. And she never forgave him.

Luc was right after all. She could have waited until they were both sixteen before she told the police that Ambrose had dis-appeared. But she did not. And so he was taken away, back to the life he thought he had escaped.

And Luc, who had killed the only real parent he ever had for love of his sister, saw her turn cold, and turn away from him. When he was sent back to France, he knew it was Kate’s doing – Kate punishing him for the murder only she knew he had committed.

I remember his cry, sobbing out in the night, I would have done anything to be with you … it was only ever you …

And I think my heart might break.

Rule Five

Know When to Stop Lying

IT IS NOT Owen who comes to collect Freya and me from the hospital – I still haven’t called him – when, in true NHS style, Freya and I are abruptly discharged at 9 a.m. the next day because they need the bed.

My phone was burned up in the house, like everything else, and they let me ring from the nurses’ station, but even as my fingers hover over his number, something inside me fails, and I can’t face the conversation we must have. I tell myself my reluctance is down to practicalities – it would take him hours to traverse rush-hour London and the snarled-up grid of motorways between us. But it’s not that – or not only that. The truth is that last night, as Freya’s life flashed before my eyes, something inside me shifted. I just don’t know exactly how, and what it means.

Instead it is Fatima I call, and as I stand outside the paediatric wing, Freya huddled in a borrowed blanket, I see a taxi pulling up, and Fatima and Thea’s pale faces at the windows.

When I climb in, buckling Freya into the seat Fatima has sens-ibly organised, I see Shadow lying flattened on the floor at Thea’s feet, her hand on his collar.

‘We were discharged horribly early this morning,’ Fatima says over her shoulder from the front seat. There are dark circles under her eyes. ‘I’ve booked us into a B&B on the coast road. I think Mark Wren will want us to stick around, at least until the police have spoken to us.’

I nod. And my fingers close over the note in my pocket. Ambrose’s note.

‘I still can’t believe it.’ Thea’s face is white, her fingers move nervously in Shadow’s fur. ‘That he … Do you think it was him? The sheep?’

I know what she means. Was it Luc? Did he do that, as well as everything else? I know they must have spent the night as I did. Thinking. Puzzling. Trying to work out the truth from the lies.

I look at Fatima.

‘I don’t know,’ I say at last. ‘I don’t think so.’

But there I stop. Because I don’t want to say what I really think. Not in front of the taxi driver. He’s not Rick – I don’t recognise him. But he must be a local. And the truth is, of all the things Luc did or didn’t do, I think that we were mistaken in suspecting him of that.

I thought that he wrote that note because he hated Kate, and suspected her of covering up Ambrose’s death. I thought he wanted to scare us into confessing. I thought he wanted the truth to come out.

But later, when Kate told me about the blackmail and the money, I started to wonder. It didn’t seem like Luc, somehow. Not that cold-blooded calculated draining of her resources. I couldn’t imagine Luc giving a damn about the money, but trying to even up the scores – make Kate pay for the suffering she had caused him … yes, that felt like something he might do.

Now though, after last night, I don’t believe it any more. It makes no sense. Luc, alone of all of us, except Kate, knew the truth, and he was lying even more than the rest of us. He was part of the Game just as much as we were and he had more to lose than any of us if the truth came out. And besides, in that long night in the hospital I have had time to think, to remember that list of convictions that Owen sent me, and one date on it sticks in my mind.