Olivia is sitting by herself on the sofa when I head back into the living room. She’s staring aimlessly towards the wall, her body present but her mind elsewhere.

‘I’m worried about him,’ she says quietly. It’s haunting: a crumbling, vulnerable tone bereft by angst.

‘At least the police are involved now,’ I reply. ‘They’ll be able to get a proper search going.’

‘I suppose.’

‘What did they ask you about?’

‘Not much. Where he hangs around, who his friends are. That sort of thing.’

She asks me to take her to work, so I do. It’s a near silent journey and I know my daughter well enough – know myself well enough – to realise that it’s not the time to push this. After leaving her at the front of the Cosmic Café, Olivia thanks me and then heads inside solemnly. I doubt even Rahul can cheer her up today.

Back at home by myself and I quickly find out that stun guns – or taser pulses, as Dan’s weapon is called – are illegal in the UK. There’s not even a grey area when it comes to civilians. I thought there might be some sort of low-wattage version allowed – but the law seems clear enough. Or Google, to be more precise. It’s an offence to possess a stun gun, let alone use it. It’s illegal to buy and sell – which means there’s nowhere in the country that Dan could have bought it from legitimately. It’s not even a trivial offence. Under the firearms act, someone in possession of a stun gun can go to prison for five years.

I find myself staring off into nothingness, much like Olivia earlier in the evening.

Five years.

Why would Dan risk something like this for five years in prison?

There’s a chance he might have confiscated it from a student. Perhaps he was concerned that reporting the find to the authorities would ruin the youngster’s life? He used some discretion, gave the student a stern warning and then… hid the gun in his gym locker…?

It’s possible. Highly implausible but possible.

I find the exact model of stun gun online, pictures and all, and it seems readily available in a handful of Eastern European countries. It can be imported from the United States as well. It would be a brave person who ordered and then sat back waiting for Royal Mail to deliver. There’d be every chance it would be the police knocking, rather than a cheery postman.

So where did it come from?

Dan gets home a little before half past nine. He’s flustered and seems tired. We make small talk over our respective days but there’s more of a distance than before – and that’s saying something. There’s a massive part of me that wants to ask him outright what’s going on but the words never quite seem to form. I’m not sure where to start.

Hey, by the way, I was snooping in your gym locker earlier and I was just wondering what’s going on with the highly illegal weapon you’re storing in there?

Ahead of the separation, we’re at an uneasy truce. If I accuse him of gaslighting, or admit to my own snooping, that’s it. There’s no going back. If I’m wrong, I’m the paranoid, unhinged spurned wife. If I’m right, what then? Can I prove anything before he gets rid of any evidence?

For Olivia’s sake, I need him. He’s her father and I have to be sure before I make any accusations.

The only thing I feel some degree of certainty over is that I’m not in danger. I’ve known Dan for more than twenty years. I’ve rarely seen him angry, let alone violent. That’s one of the things that annoys me the most. I might raise my voice, shout, scream, throw around an insult or two. He’ll sit there calmly listening to it all and then reply with perfect composure. It’s infuriating. I always seem like the deranged one.

Despite that, he must sense something isn’t as it should be. He asks if everything is okay and I palm him off by saying the police were round to ask about Tyler. I say they need to talk to him at some point and that I passed on his mobile number. I watch for a reaction but there’s nothing except an accepting nod. He asks if I have the details of the investigating officer – and says he’ll call tomorrow. All very straightforward. No drama.

Being in the house alone with him doesn’t feel quite right, so I say I’m going to nip to Ellie’s for an hour. It’s late – but he doesn’t object. He replies that he’s got a little bit of work to finish and that he’ll probably be in bed by the time I return. This is how we’ve been for months… years. He does his thing, I do mine. Occasionally we cross over but not really.

I text Ellie, telling her to put the kettle on, and then set off along the street. Her house is only five minutes but I walk more slowly than usual, looking for things on the route that I take for granted. This journey is the last one Tyler apparently made and I find myself noticing the cut-throughs I’d normally pass without hesitation.

There’s surprisingly few places he could have deviated from the route back to the High Street. One of the cut-throughs loops back to the furthest end of our road and then there is the row of houses that leads to the crossing before I get to Ellie’s road. The junction is the first place he could realistically have strayed onto a different path. One road leads to the High Street, one to our house, one towards Ellie’s, and the final one towards the dual carriageway.

I stop and look up at the lamp posts, checking for CCTV. It’s everywhere in the cities – but not here. North Melbury is too small, too inconsequential. There’s almost no late-night trouble. Major news stories are a noisy cockerel waking people up on a Sunday, or the weather forecast for the summer fete. I can’t remember anyone going missing around here.

Ellie opens the door herself when I knock. She’s in a different set of pyjamas from the other day, along with fluffy bunny slippers. She says hello but then groans when she turns, stopping to rub her breastbone.

She leads me through the hall into the kitchen and slumps into a seat at the table. ‘Forgot my painkillers again,’ she says.

‘You should set an alarm on your phone to remind you.’

She starts to shake her head and then catches herself. ‘I’ve never really liked taking pills and other medicines. You know what Ma was like.’

I do know what her mother was like – but had largely forgotten. Ellie’s mum was always taking something, be it a miracle youth potion she’d seen on television, or some homeopathic nonsense she’d been sold along with the drum of snake oil. I’m not sure what she was hoping to achieve – but it didn’t do much good in the end.

‘Jason’s in bed,’ Ellie says.

‘I was here to see you.’

‘Sure it’s not to get away from Dan?’

The smile is knowing. She can see right through me.

‘A little from column A…’

I laugh and cross to the kettle, asking Ellie if she wants a tea. She says there’s wine in the fridge if I fancy it – but my mind is muddy enough. Alcohol is the last thing I want.

Ellie is still working on her jigsaw but it’s not that much further along than it was when I saw it last. She has got the straight pieces along the sides all in place. The box is on the table, leaning against the wall with a photo of a canal. It’s a night scene, lights streaming down from windows above as a narrow boat drifts along serenely. I think it’s probably Venice but I’m not sure and have never been. It’s beautiful and, wherever it is, I wish I could see it for myself.

‘How’s Olivia?’ Ellie asks. ‘She cancelled our accounting session earlier.’

‘Did she? I didn’t know. The police were over to talk to us about Tyler – so it was probably because of that.’

I empty the recently boiled kettle into two mugs and then realise I haven’t answered the question.

‘She’s upset,’ I say. ‘It’s been five days since he was last seen and it’s gone a bit beyond his usual disappearing acts.’

‘What do you think?’

I return to the table and cradle the mug until the heat makes my fingers tingle. ‘I don’t know. I assumed he’d be back by now. I don’t know enough about him to know what might have happened. I told them about his cannabis, so perhaps they think he owed money, something like that…’ I tail off and run a hand through my hair, tugging at a knot that has appeared. ‘If it is drugs, I hope Liv isn’t involved.’

Ellie touches my wrist. ‘I’m sure she’s not.’

‘I feel like an awful mother. I don’t know how it’s come to this.’

When I look up, Ellie is tight-lipped and I realise my mistake. She can’t have children. Her mother died of ovarian cancer and Ellie had hers removed as a precaution. Olivia called her ‘Auntie Ellie’ for years – but that’s as close as Ellie got to a child of her own.

‘Sorry,’ I say.

She blinks and, for a moment, she’s no longer in the room. She breathes and then the moment has gone and she tells me it’s fine. I know it’s not. I’m usually careful with what I say around Ellie but I’m shattered from the past few days.

‘Liv was talking about the mill,’ I say lightly, trying to make it sound like a joke. ‘I didn’t know you were telling her our secrets…?’

Ellie bats it away with a wave of her hand. ‘It sort of… came out. She was saying how you didn’t like Tyler and I told her it wasn’t that straightforward. I said we used to get up to all sorts when we were her age and that you were concerned. I hope you don’t mind. I was trying to help.’

She doesn’t look up, reaching for a piece of the puzzle instead and slotting it into place. I guess there’s nothing wrong with what she told Olivia.

‘It’s like the boy who cried wolf,’ I say. ‘Liv and Tyler break up and there’s a week of devastation, then it’s all fine again. I don’t know if I believe he’s missing in the sense that people go missing. He might be at some hippy weed festival in a field somewhere.’

Ellie winks: ‘Sounds like fun.’

‘Not at our age.’

‘Speak for yourself.’

It’s good to talk about this. A small part of that weight is finally shifting. ‘I’ve got a feeling he’ll waltz back into everyone’s lives in a day or three as if nothing’s wrong.’

I’ve been looking at the puzzle, trying to see if I can help. Rather unhelpfully, all the water pieces look the same – which I guess is the point. I glance up and realise Ellie is staring at me.

‘What?’ I ask.

‘Can I say something?’

‘I think we’ve known each other long enough for that.’

She bites her lip. ‘It’s just… you don’t seem massively concerned.’

‘About what?’

‘Tyler.’

As always, she’s seen right through me. I spoke to the police; I’ve tried to say the right thing to Olivia… but it’s forced. None of it is real. I glance off to the fridge, the wall, the window. Not making eye contact.

‘Does that make me a horrible person?’ I ask.

A shrug. ‘You tell me.’

It takes me a few seconds to find the words. ‘It’s not like I wish he was dead or anything. It would just be nice if he sort of… sodded off and left Liv alone.’

‘He’s done the sodding off part.’

I’m not sure if she’s joking: I’m playing with my hair again but catch myself this time. It’s the type of thing that annoys me when other people do it, so I stop. There’s a bump from upstairs – Jason, presumably – and we both stop for a moment.

‘I hope Tyler’s safe,’ I reply. ‘I honestly do… but I kind of wish he was with another girl. Something like that. It’ll turn out he’s got someone else pregnant and she’s busy having the kid. Something big that will make Liv walk away.’

I realise what I’ve said but it’s already too late. More children talk.

Ellie doesn’t seem to mind this time. She’s back to the puzzle. ‘You got work tomorrow?’

It’s a tactful – and timely – change of subject. I tell her I do and then we’re uncharacteristically silent for a minute or two. I slot a piece into the puzzle and then accidentally knock another onto the floor, before retrieving it.

‘Can I tell you something?’ I say. It’s me who’s fumbling this time.

Ellie looks up from the table and we lock eyes for a moment. ‘Of course.’

I take a breath and can’t keep the eye contact. There’s so much I could tell her. So much I want to tell her.

‘I lied to the police.’

The words hang between us like a knife on a rope swinging back and forth. Something dangerous that could go either way. I can’t believe I’ve said it.

‘Not lied,’ I say. ‘I didn’t tell them something. Kept it back. I don’t know if that’s lying.’

‘About what?’

‘They were asking about Tyler, about how we argued over his lack of job and Olivia’s money. They asked where I’d been since Saturday. I told them I was in a hotel on Monday night, it’s just…’

I tail off, wishing I’d said nothing. It’s too late now, of course. Ellie edges forward a minuscule amount, hanging on my words.

The memory wasn’t clear at first. In the aftermath of waking up in that field, everything was blurred and hazy. It’s not soap opera amnesia in that I’ve suddenly remembered everything I’d forgotten, but the pictures have sharpened and smoothed.

‘I was with another man,’ I say.

Nothing happens for a moment. It feels real now I’ve said it out loud. I’ve sort of known it since waking up in that field – but knowing and admitting it to myself are two different things.

When it comes to separation, to Dan’s possible infidelity – which is based on nothing other than the way he looked at Alice – I’ve been able to take a high ground. But after the night in the hotel, there’s a part of me, perhaps a big part, that wonders if I’m the bad person here. Perhaps it’s not a fifty-fifty thing in that Dan and I were never matched. Perhaps he’s a perfectly loving husband and father – and it’s me who’s destroyed everything. That’s who I am and what I do.

‘Wow,’ Ellie says.

‘Maybe not with another man,’ I add quickly. ‘Not like that. I don’t remember everything… I remember bits…’

Ellie takes a second or two to reply, picking her words. ‘Does Dan know?’

‘No.’ I pause and glance towards the hall, wondering if I heard a creak from the stairs. ‘I’m not sure Dan would care.’

‘So what have you done wrong?’

‘It’s not much of an example for Liv, is it? We’re separating and trying to do it amicably. Irreconcilable differences is one thing; adultery is something else entirely.’

Ellie has a gulp of tea and then clanks the mug back onto the table. She walks around me very deliberately and pulls the kitchen door closed with a quiet click. Perhaps the creak from the stair wasn’t in my imagination.

‘How did it happen?’ she asks.

I don’t want to talk about it – but can hardly back away now.

‘I was at the hotel to meet a client but he didn’t show up. He texted to say he was running late and then that he couldn’t make it at all. I was waiting in the bar. One drink became two and then I got talking to this guy. He bought me another drink and then I insisted on buying him one. One thing led to another and then we went upstairs…’

Ellie is silent for a moment but then she reaches across the table and grips my hand. The veins in her fingers are a vibrant blue but the skin is smooth. An accountant, not a builder.

‘Did the police ask if you were alone in the hotel?’

‘No.’

‘So you didn’t lie. You’re clear with them – and, for Dan, you’re separating. The only reason you’re still living together is because it’s taken time for him to find a flat. If it wasn’t for that, you’d be apart anyway. If he meets someone else – or you do – then that’s fine.’

It sounds logical and reasonable. It is a matter of timing. If Dan had found a flat more quickly, we would be living apart already. We’ve not discussed precisely what the separation means, although there’s an understanding that it’s a prelude to divorce. Neither of us believe we’ll spend a month apart and suddenly fall for each other all over again. So, with that, why would either of us have a problem with the other having a relationship with someone else? Living together now is about timing and the divorce will be paperwork. Emotionally, we’re already separate.

The problem is that this is about more than that. It all is. I woke up in a field in a car drenched with blood. I have no idea if that’s connected to the man at the hotel, or, indeed, what happened after we went up to my room.

I want to tell Ellie this as well – except I can’t. It feels like a secret only for me.

There’s no chance to elaborate anyway because my phone starts ringing. Olivia’s name flashes – which is unusual because she rarely calls. It’s all texts, emojis and acronyms I don’t understand. I have to google them to figure out what it all means.

‘Hi,’ I say.

Olivia’s voice quivers as she replies.

‘I need you,’ she says. ‘I need you now.’