'Why did you want the CCTV film on that memory stick?' I ask.

'Because it's incriminating to Art,' Morgan says softly. 'After Rodriguez told me you'd stolen it, I had to get it back to protect him.'

'Protect Art?' I shake my head. 'I don't get any of this, Morgan. Art's your brother. What have you got to do with our . . . our baby?'

Morgan taps her elegant feet on the floor. She seems to be considering something.

'I would have spared you this, Geniver,' she says. 'But, frankly, right now I'm so angry with you I don't care any more.'

'Spared me what?'

Morgan points to the door. 'This way,' she says. 'I'll show you.'

I glance round at Lorcan. He's rocking more wildly in his chair now, clearly not wanting me to leave. But I don't see that I have a choice. Even if Morgan isn't armed, Jared has that gun.

Anyway, I'm desperate for answers.

I walk into the kitchen and past Jared. Morgan removes her cap and blonde wig and lays them on the counter. She directs me through the kitchen, out into the hallway and into a living room. It's a large, square space, full of the same pear-wood furniture as much of the rest of the house. A large-screen TV stands in the corner opposite a leather couch. Two sleek armchairs sit on either side of the sofa. It's a more lived-in space than the rest of the house. Books and magazines are spread across the coffee table and a stack of children's DVDs teeters on the floor in front of the TV.

Morgan crosses the room, pushes the DVDs aside and opens the cupboard underneath the TV. She draws a disk from her coat pocket and places it into the machine, then she steps back.

'This is a copy,' she says. 'The original was made on video.'

'Original of what?'

'You'll see.' She faces the screen. 'This is who your husband really is, Geniver.'

As the screen fizzles into life, I get the impression Morgan's in her element. That, despite what she says, she's been dying to show me whatever is on this disk. A picture appears. It's grainy . . . colour, but poor-quality a shot of a bedroom, a girl's bedroom, with white lacy drapes around the bed and a row of dolls propped on the pink-painted shelf above it. A warm pink light glows from the bedside lamp.

'What is this?'

'My bedroom at home in Edinburgh. I was home from college the Easter holidays. I was nearly twenty.'

I stare at the screen, my heart beating wildly. What the hell amI about to see?

A very young Morgan fills the screen, backing towards the bed. Slim and tanned, she looks amazing, dressed in a mini-skirt and a pink top with thin straps. There's a softness about her I've never seen in all the years I've known her. She's smiling at someone beyond the camera, flicking her dark hair longer than it is now off her shoulder.

She sits on the bed and holds out her hands. Art walks into the frame. He's wearing jeans and a T-shirt and looks unbelievably young. I frown, trying to work it out. If Morgan was almost twenty here, then Art must have been eighteen. He sits on the bed so both of them are side-on to the camera. Neither of them looks at it. I'm certain Art has no idea it is there. He would hate the idea of being filmed. He reaches out and pulls Morgan towards him. They kiss.

My stomach retches. I look away.

'What is this?' I say. 'Why are you-?'

'Watch!'

I turn reluctantly back towards the screen. Art is peeling Morgan's top up, his mouth is on her breast, one hand fumbling under her skirt. Morgan's face is tipped back, her hair sprawled over the white bedspread. She looks ecstatic.

A furious mix of hurt and jealousy and repulsion surges through me.

I turn back to the Morgan in the room beside me. She's watching my face, a mean, thin smile curling about her lips.

'This is what you wanted to show me,' I snap. 'It's disgusting.'

'It wasn't disgusting.' The smile falls from Morgan's lips. 'Certainly a lot less disgusting than you and Lorcan sneaking around in shabby hotels. Art and I loved each other.'

'What?' The ecstatic look on the younger Morgan's face flashes before my mind's eye. 'Maybe you had some revolting crush on him, but he must have been drunk to have . . .' I'm trying to keep my eyes off the screen. I don't want to see what I know the film shows. But I can't resist a quick glance. It's enough to confirm what I've already imagined. I look away again, quickly, but the image of Morgan and Art together has seared itself on my brain.

'Art wasn't drunk.' Morgan snaps. 'That wasn't the first time we made love, either. We did it every time my parents were out. We couldn't keep our hands off each other.'

'But he's your brother.'

'We'd only just met,' Morgan says impatiently. 'Art had turned up at the house the week before. Daddy refused to speak to him but Art insisted, and there was a big row at the front door. I was watching from upstairs. Heard everything. I was almost twenty by then and knew the rumours about Daddy having other women, so it wasn't hard to work out what was going on. Then Art left. I ran after him.' She pauses. 'Remember, I told you all about that, didn't I?'

I refuse to nod, but of course it's true. Morgan did tell me so vividly that I could almost see her flying out of the house in tears, offering support and friendship. The sister Art had never known. And I'll never forget the hurt on Art's face when I finally got him to talk about it at how cold his father had been . . . how desperately rejected Art had felt.

It hadn't occurred to me for a second that there was more to the story than two children united against a bullying father.

'We talked for a bit, then we met later,' Morgan says. 'One thing led to another. It was chemical. Inevitable.'

'And wrong.' I feel sick to my stomach.

Morgan raises her eyebrows. 'Who are you to judge us?' she says. 'Who is anyone to judge us?'

'Why did you do the tape?' I ask. 'Art didn't know you were making it, did he?'

Morgan shrugs. 'We'd met every day for nearly a week. Then Art had to go home and I realized that I wanted a proper memento to remember him by.' A blush creeps across her cheeks.

I stare at her, realising what she means. 'You really fell in love with him,' I shudder, horrified. 'Oh, my God, you-'

'I got pregnant.' Morgan's words cut the air like a whip. 'I was pregnant with Art's baby. But he said we couldn't keep it. That he loved me but no one would accept the baby.'

My chest tightens. For a second it hurts so badly I can't feel anything else.

'What happened?'

Morgan keeps her cold gaze fixed on my face. 'I did what he wanted. I had the termination. Something went wrong some rare, one-in-a-million, chance thing and the doctor told me I'd never be able to have any more children.'

The film on the TV in the corner is over. I can hear the white noise fizzling away. It's too much to take in. 'An abortion.' The words whisper out of me. 'Morgan.'

She grimaces. 'It was the worst time. I told no one. No one apart from Art ever knew. But I knew. I knew as soon as I'd done it that I'd made the mistake of my life.'

'Oh, God.' My hands are over my mouth. Surely this is a nightmare. Surely in a second I will wake up.

'I was lost for a while,' Morgan says, her voice low and sad. 'I didn't see Art again for four years the next time was when he and Lorcan went to the States. I said they could stay in the house at Martha's Vineyard then I made sure I was over there for their visit. I couldn't believe it when they turned up. Art was a mess. Doing drugs. No direction. A total mess. And Lorcan was such a loser . . .' She pauses. 'I pleaded with Art to clean himself up. I offered him as much money as he wanted, but Art was too proud. The next time I saw him was two or three years after that. He'd turned things around. He'd set up Loxley Benson. He kept talking about you . . . this girl he'd met . . . but I knew, even though Art couldn't put it into words, that the feeling between us was the same as it always had been. And, as soon as I heard you were pregnant, I knew that Art owed us that baby.'

I can't breathe. So this is what Art meant when he said our baby was 'atonement'. A new life for a lost life.

'But it was our baby,' I gasp. 'Mine and Art's.' My mind scrabbles frantically to get a purchase on what I'm being asked to believe. How could Art have given Ed up like he did? For love? No, he loved us. He wanted us to have a baby . . . still wants us to have a baby.

'Art agreed I should take Ed,' Morgan's expression is proud, defiant. 'He helped make it happen. He even gave you the zolpidem that sedated the baby the day of the c-section. He slipped a tablet in with your vitamins.'

I stare at her, my mind rushing back in time. So that was why I'd felt groggy and lightheaded all day. Art had drugged me, tricked me. It's unbearable.

'And Art did all that for me,' Morgan goes on. 'He knew I'd be a wonderful mother.'

'But what about me?' I insist. 'Didn't you stop to think for a second that letting me think my baby had died was cruel? Inhumane? Unfair?'

Morgan smiles again. 'Daddy's favourite saying when we were growing up was: "Who told you life was fair?" It isn't. You get what you can, when you can. It's all about survival. And the only thing that gets you what you want is money.'

'That's rubbish.'

'Is it?' Morgan arches an eyebrow. 'Money paid for Doctor Rodriguez to fake a stillbirth certificate. Money paid to keep staff at the hospital and the funeral home quiet. Money paid for all the papers I needed to prove Ed was mine. And money kept the trail secret until you and that idiot O'Donnell tracked us down to Shepton Longchamp.'

The image of Bernard's lifeless body flashes in front of my eyes.

'I know you killed him,' I say. 'And his wife, Lucy.'

'Don't be ridiculous,' Morgan sneers. 'O'Donnell was an accident. I . . . I panicked and pulled the trigger. I had nothing to do with his wife.'

'Not directly,' I said slowly. 'But you sent Jared, didn't you? You sent your driver, to run her down.'

Morgan stares at me. Her eyes give nothing away.

'How could you, Morgan?' I say. 'The O'Donnells were good people. They were just trying to help me find my child.'

'Good people?' Morgan folds her arms with a disdainful sniff. 'They were after Art's money.'

'No. No way.'

'You sure about that? Think, Geniver. Are you seriously saying that, when you spoke with the O'Donnells, the subject of a reward never came up? Do you think that they would have bothered to report Mary Duncan's deathbed confession to you if they hadn't known Art was a successful businessman worth a small fortune?'

I think about Lucy's anxious face, blushing as she confessed her money worries, and Bernard's embarrassed relief as I paid him twenty grand.

'Hoping for money doesn't justify murder,' I say, holding my voice steady. 'And what about Gary Bloode, the anaesthetist? You had him killed too, didn't you? What did he do, threaten to expose you?'

'Bloode got greedy,' Morgan snaps. 'He demanded more money than I was prepared to pay.' She pauses. 'You see, Geniver? None of them was innocent. And only the truly innocent should be protected.'

'Like children, you mean?' Anger rises in me again. 'How exactly have you protected my son by keeping him away from his own mother?'

'I am his mother.' Morgan fixes me with steel in her eyes. 'Ed doesn't lack anything.'

'Who else knows?'

'No one apart from us and Art.'

'So money buys you everything,' I say sarcastically.

'Almost everything,' Morgan says without irony. 'Art comes to see Ed and me whenever he can. That's love.'

Fury boils inside me again. 'Ed was my baby, Morgan. Mine and Art's. How can you live with that?'

'I've lived with far worse.'

A long silence falls over the room. It's raining outside dark through the bare windows. I shiver, even though it's not cold in the living room. I don't believe Art loves Morgan. Not like she claims. So why did he let her take our baby? Morgan walks to the DVD slot and ejects her disk. An image from the film burns its way into my head.

'You threatened him, didn't you?' I stammer, working it out. 'You said you'd show people that film if he didn't give up our baby.'

'It wasn't that simple.'

'Yes it was. You used that film to blackmail him.'

Morgan's expression is ice-cold. 'You don't know what you're talking about.'

'Yes, I do.' I push on, sensing I'm right. 'You know that film really just shows two confused, screwed-up teenagers who let their hormones get the better of them. But you used it to punish Art for . . . for not loving you as much as you loved him.'

Morgan says nothing but I can feel I've hit home.

She places the DVD in her coat pocket, then indicates the door.

I think back to what Art told me in the woods. Was any of that true? He certainly didn't mention the film of him and Morgan. 'So . . . back then, when I was pregnant, did you threaten to hurt me if Art didn't give up our baby?'

'Is that what he told you?' Morgan sniffs. 'Poor Art. No. Art gave me Ed because he loved me.'

'Not because you threatened to hurt me if he didn't? Not because he threatened to show people this film of the two of you?'

'You didn't come into it. And the video wasn't the main issue. It was . . . just my safety net, like the CCTV film of Art at the Fair Angel was Rodriguez's. But yes, Art definitely didn't want people knowing about . . . what we did.'

Even me.

'But I would have understood if Art had just told me.' The words blurt out of me but I'm not sure they are true.

Morgan laughs scornfully. 'Listen to yourself, Geniver. Do you really think it was your reaction Art was worried about? You were a long way down the pecking order, believe me. Art is the head of a company built on ethical practice. If the film of us together had got out, it would have ruined him.'

I stare at Morgan. Whatever she says about Art loving her, and whatever he says about trying to protect me, this is surely at the heart of his actions. I can just see the way the press would have presented the scandal eight years ago when Ed was born. They would have emphasised the hypocrisy of Art's ultra-ethical public stance and highlighted all the sordid details, using the video as proof. It would have ended his career, just as it was taking off.

My legs threaten to give way underneath me. All the lies. All the pain. To enable Art to retain his status as an ethical businessman . . . so that Art's ruthless drive to the top remained unimpeded. I want to yell at Morgan that what she's saying isn't true. But I know Art too well for that.

Some terrible dark place, deep inside me, cracks and bleeds.

'All for power and money.' The words slip out under my breath.

'Obviously I took care of the money,' Morgan says, misunderstanding what I've said. 'Art helped. We paid everyone in cash. Over a million altogether.'

My head reels. The 50,000 Art paid MDO for Hen suddenly seems inconsequential. And innocent. Oh, Hen, I think to myself. I'm sorry.

'You just don't understand Art. Not like I do,' Morgan says, tight-lipped. 'He's like our father was a huge, huge man who can't be tied to convention. He loves me with a power you can't even imagine. We love each other.'

I shake my head. Morgan indicates the door back to the hallway. 'Now you know how everything started,' she says. 'It's time for this to end.'