I jog up the hill to my car, trying not to cry. My whole body trembles. Darcy is a murderer, I know she is. And now she has my son. Should I call the police? What if it really is a misunderstanding and Jared arranged for Darcy to pick him up? I’ll kill him if he did, but I’ll also be relieved because then it won’t mean that she’s taken him without permission. If this is Jared’s doing, the police will think I’m a deluded crazy person. They might arrest me again or lock me up in an institution like they did with my birth mum.

I slow down for a moment, trying to get my jumbled thoughts straight. This can’t be Jared’s doing – Darcy forged a note. My brain is racing, spinning. Am I crazy? Actually, it doesn’t matter – not when Joe is involved. If there’s the tiniest chance that he’s in danger, I have to try to save him, even if I’m wrong and end up having everyone think I’m mad.

A thin skin of ice coats the car, glistening under the streetlights. I open the door and slide into the driver’s seat, putting a call through to Jared at the same time. I growl in frustration as it goes to voicemail. I end the call and redial. Voicemail again. I end the call again and redial, praying for my husband to answer this time. Bloody voicemail again.

‘Jared, please get back to me.’ I sound shrill and wavery. Unhinged. But I can’t make my voice any calmer. ‘Did you arrange for Darcy to collect Joe from school tonight? I thought we agreed that I would pick him up. Call me back, urgently.’

I shove my phone into my bag, chuck my bag on the passenger seat and start up the engine. Then, I put the car into first gear and press down on the accelerator. I release the handbrake too quickly and roll backwards, almost smashing into the SUV parked a few feet behind me. Luckily, I stomp on the brake just in time.

I take a breath, pull on the handbrake and sit still for a minute, my hands gripping the cold wheel, desperately trying to calm down. It won’t do Joe any good if I end up having a crash. I try again. This time easing out of the space without mishap. I’m going straight over to Darcy’s. The bitch better be in and she better not have harmed a hair on Joe’s head. I barely register the short drive over there. The roads, the lights, the cars – they’re all just a blur through a haze of anxiety as I mutter to myself, head swimming, fingers shaking.

Almost there.

The automatic gates are open, thank goodness. I tear down the driveway, her fancy, contemporary garden lamps lighting my way. If I wasn’t in such a hurry, I’d want to smash into each one, uprooting them, destroying her perfect driveway.

She’s there, standing in the doorway under the porch light, the chill wind blowing her hair. As if she’s expecting me. Dressed casually in jeans, boots and a white t-shirt, she must be freezing. No sign of Joe or Tyler.

The car skids on the driveway as I pull on the handbrake too soon, like a boy-racer in a deserted car park. I grab my bag and car keys, fling open the car door and almost fall out onto the driveway in my haste to get answers.

‘Where’s my son, Darcy?’ I cry. ‘If you’ve hurt him… if you’ve so much as harmed one hair on his head, I’ll—’

‘Calm down,’ she says, raising her eyebrows as if I’m some minor inconvenience. ‘Joe’s fine. Come in.’

‘How dare you take my son out of school without permission. How bloody dare you.’ I’m shaking with anger while she is cool and composed, admiring her nails.

‘I thought I was helping,’ she says. ‘Are you coming in, or not?’

‘Helping? I don’t think so.’ I shoulder past her into the hallway lit by a huge crystal chandelier. ‘Joe!’ I yell. ‘We’re going now!’ My heart pounds as I listen for a reply.

Darcy closes the front door and strolls past me into the kitchen.

‘Where’s Joe?’ I call after her. ‘Are they upstairs? In the garden? Get him now, Darcy. This isn’t funny.’ I dump my bag and keys on the hall table and follow her into the dimly lit kitchen, scanning for any sign of my son. But it’s quiet. Still.

‘Marianna’s taken the boys out for ice cream and then to the movies,’ Darcy says. ‘So you don’t need to worry. They’ll be in heaven.’

‘What! You mean they’re not here?’

‘That’s what I just said.’ She heads over to the black marble island in the centre of the room. It’s dark, apart from a couple of central pendants illuminating her workspace. Two huge beef tomatoes sit on a chopping block next to a black-handled knife. She grasps the knife and slices into one of the tomatoes, the knife going in smoothly. ‘I’m making a salad,’ she says. ‘Care to join me for supper while we wait for them to come home?’

‘No I bloody don’t want to join you for supper. I just want my son.’ I clench and unclench my hands by my sides impotently. ‘Darcy, why did you take my son out of school?’ As I wait for her to answer my question, the blood whooshes in my ears and my heartbeats fill the pregnant silence.

‘I needed to get you over here,’ she finally replies. ‘But I didn’t think you’d be quite this keen. I think you might have left skid marks on the driveway.’ She laughs at her little joke.

I don’t find anything she says funny any more. ‘You needed to get me over here? What do you mean? Why didn’t you just call me?’

‘No, that wouldn’t have worked. I couldn’t risk my call being traced.’

A chill sweeps through my body. What’s she talking about? ‘Call Marianna!’ I cry, hearing the shrillness in my voice. ‘Get her to bring Joe home, right now.’

‘Oh, they’ll be in the movie theatre already. Her cell will be switched off. You’re not allowed to have your phone on once the movie starts. Or are you one of those selfish types who keeps it switched on? It’s very annoying, you know. You’ll be in the middle of a tense scene, and then someone’s phone starts ringing. Takes you right out of the moment.’

‘What the hell are you on about? Try her phone,’ I demand. ‘Call the cinema and tell them it’s an emergency.’

‘No,’ she says, her eyes glinting.

‘Fine. Then tell me which cinema, and I’ll go and collect him.’

‘No.’ She smirks and laughs, and I can tell there’s something really wrong with her. Something rotten.

‘Okay,’ I say, my voice trembling. ‘Then I’ll go and find him myself. And if he’s not at the cinema, I’ll call the police and tell them you abducted my son.’

‘No,’ she says softly as she turns towards me with the knife in her hand. Tomato juice drips from the blade onto the white marble floor.

Surely she wouldn’t try to… But I remember Mike’s blank eyes, the blood everywhere, and I know without a doubt that she killed him. I glance to my right and see the bifold doors are closed tight. Probably locked, I can’t get out that way. I’ll have to go back through the front door. The same way I came in. I turn and run, fumbling with the front door, shoving it open. I head straight for my car, her laughter chasing me out onto the floodlit driveway.

Too late, I realise my keys are with my bag on her hall table. I swear under my breath. Darcy’s footsteps are close behind me. I can’t turn back now. Instead, I swerve and make a run for it, racing around the side of the house, my heart battering my ribcage. A security light flashes on.

‘I can see-ee you!’ she calls, enjoying my blatant fear.

The freezing night air takes my breath and chills my tears of terror. I make my way down the side path, past the white-rendered wall of her house, tall, dark pine trees on the other side, her steady footfalls behind me. I have no idea if this path leads anywhere, or if I will find myself at a dead-end, with a wall in front of me and a mad woman brandishing a knife behind me.

Luckily, it’s not a dead-end. The path leads to the decking area behind the house. Through the closed bifold doors, I glimpse the half-lit kitchen. There’s no time to look behind me. I have to find a way out of here. The wooden deck is slippery, a thin film of ice forming on its surface. I skid and slide across it, stumbling down the wooden steps and almost falling head first onto the grass below, the place where Tyler and Joe played their game of football all those weeks ago when I first got caught up in Darcy’s web.

‘You can run, but I’m gonna get you, Louisa,’ she calls out from behind me.

The icy, brittle grass crunches underfoot as I race towards the gate, set into the white wall that leads onto the beach. Security lights click on, illuminating my progress, like moving spotlights on the star of the show. I crash into the wooden gate at the end of the garden, pushing and pulling at it in desperation. It won’t budge.

‘Don’t strain yourself,’ Darcy calls out, amusement in her voice. ‘It’s locked!’

I’m unfit. Un-athletic. Weak. And my knee is shot to pieces. But somehow I scramble up and over the high gate, tearing my nails in the process. I guess fear of death is a powerful motivator. I land on the hard sand with a thump, pausing for only a few seconds before struggling to my feet and limping away across the sand dunes.

She’s behind me. I hear her laughter, her fragmented taunts whipped away by the wind. As I stumble across the dark sand, I picture the knife in Darcy’s hand. The sharp edge of the steel, the glint of the blade. Again, I remember the sight of Mike’s body covered in blood. Will that be me soon? Lifeless and bloody? My knee feels torn and ragged, the pain a throbbing precursor to what is about to come. It hurts so much, I don’t know how I’m even still running. Will it hurt to die? To be stabbed in the chest? Or will the shock blot out the pain?

The swish of the waves merges with the thump of my heart. It’s never beaten so loud before. Like a war drum, a death knell in my throat. I daren’t look round. What if she’s there, right behind me, ready to tackle me to the ground? She may be slim, but she’s tall, strong, sinewy. She could beat me in a fight, I’m sure of it. Especially armed with a knife. In my mind, I see Darcy’s mocking face. The glint of steel in her hand. Will she catch me any second and stab me in the back?

I have to run faster. My breath comes in wheezing gasps, my lungs bursting, thighs burning. The cold wind stinging my cheeks, boots thudding unsteadily across the hard sand. To my right, the rolling sea. To my left, the millionaire mansions in the distance shimmering as fear blurs my vision.

A shape looms up ahead. It’s a man walking towards me.

‘Help!’ I cry, my voice half-strangled.

The man stops. Comes into focus, the three-quarter moon throwing his face into relief. Thank God. Thank God. It’s Max. He must have ignored my request for him to stop following me. Sobbing with relief, I stagger straight into his arms and he gathers me into the safety of his solid body.

‘She’s coming!’ I pant. ‘Darcy. She’s got a knife. We need to get out of here. Have you got a car?’

I try to step back out of his arms, but he’s still cradling me.

‘Max, didn’t you hear me? She’s got a knife. Let’s go. We need to run.’

His grip tightens. I try to lever my body away from him but it’s like being held by warm stone. He’s unmoving. Through my panic, I’m trying to make sense of it. Does he want to confront her? Another, more distressing thought cuts through. I push my hands against his chest, twist my body back, then kick him in the shins, but still he doesn’t move.

‘Shh,’ he says, his soft voice merging with the crash of the waves. ‘Don’t struggle. You’ll only hurt yourself.’

The sound of Darcy’s laughter comes to me through the salty air. ‘Oh, Louisa,’ she says, her voice closing in, ‘you are funny. Thinking you could ever outrun me with your gammy knee. And I see you’re already acquainted with my brother. Actually, I think he’s got a bit of a soft spot for you.’

Her brother? ‘What?… I…’ and then the penny drops. Max was working with Darcy the whole time. He’s her brother. He’s her bloody brother. My shoulders sag. So everything Max told me was a lie! I’ve been so stupid. So gullible. No wonder Darcy’s laughing at me. I’ve been played so beautifully. She’s been several steps ahead of me this whole time. And I thought I was actually making progress, getting her out of my life.

‘Max is your brother,’ I say, my shoulders sagging.

She tuts. ‘That’s what I just told you, isn’t it? You’re a little slow on the uptake today, Louisa. I needed him to keep an eye on you this week. To see what you were up to. Find out your plans. That’s when I had the fabulous brainwave of promoting him from being your stalker, to being your friend. Clever huh?’

But she’s American. And Max is English. How can they be related?

Max eases me around so I’m facing Darcy, his arms still circling my body like chains. The moon illuminates her face, eyes gleaming, hair shining. She’s not even mildly out of breath, while I’m still wheezing like an elderly, asthmatic cat.

‘I’m going to enjoy the next part of this evening,’ she says, dropping her smile. ‘Let’s get you back into the warm, Louisa. Look at you, you’re shivering.’