‘Oh my God these are good. I mean, don’t get me wrong, I like triple lard-cooked gastro chips as much as anyone … but proper seaside chips …’

Thea nods, but she’s not really eating. She’s picking at her chips, pushing them around, turning the paper wrapping translucent with fat as she presses them into the absorbent paper.

‘Thea, you’re not trying to soak the fat out of the chips, are you? You realise they’re chips? They’re fried. That’s kind of the point.’

‘Nah,’ Thea says, but she doesn’t look at me. ‘Just not that hungry.’

I shut my mouth, and for a minute I’m back at school, watching helplessly as the school nurse calls Thea in for the weekly weight check, and she comes back spitting and raging about threats to call her dad if she loses any more weight.

I wish more than anything that Fatima were here. She would know what to say.

‘Thee,’ I say. ‘Thee … you have to eat.’

‘I’m not hungry,’ she says again, and this time she pushes the paper of chips away, and her jaw juts dangerously as she looks at me across the table. ‘I lost my job, OK?’

What? I’m not sure if I’ve said the words aloud, or just thought them, but Thea replies as if I have spoken.

‘I lost my job. They sacked me.’

‘Because of … all this?’

She just shrugs, her mouth twisting unhappily.

‘Because my mind wasn’t on it, I guess. Fuck ’em.’

I am groping for what I should say – what I can say – when Freya gulps, stirs and wakens. She holds up her arms to be picked up and I pull her out of the buggy straps and into my lap, where she smiles up gummily at me and Thea, looking from one face to another, her eyes darting back and forth. I can see her little mind working … mother … not mother. Mother … not mother.

Her eyes are wide, entranced by it all – the bright chrome counter, Thea’s wide hoop earrings, flashing in the fluorescent lights. Thea reaches out a tentative hand to touch her cheek – and then the bell above the shop door pings, and we turn to see Fatima slip inside, grinning, although she looks tired and worried beneath the smiles.

‘Fatima!’ I stand, giddy with relief, and give her a crushing hug. She hugs me back, and then leans down to hug Thea, and slides into the seat next to her.

‘Have a chip,’ Thea says, pushing the paper across to her, but Fatima shakes her head, a little ruefully.

‘Ramadan, innit? Started last week.’

‘So you’re just going to sit there and watch us eat?’ Thea says with incredulity. Fatima nods, and Thea rolls her eyes. I bite down the urge to tell her she can hardly talk.

‘Them’s the breaks,’ Fatima says matter-of-factly. ‘Anyway … I have to get back for prayers and iftar –’ she looks at her watch as she speaks – ‘which doesn’t give me much time before the train back, so can we cut to the chase?’

‘Yeah, spit it out, Isa,’ Thea says. She takes a sip of water, eyeing me above the bottle. ‘I’m hoping it was something pretty fucking special to drag us down here.’

I swallow.

‘I don’t know if special is the right word. But it’s important.’

I need you. Those three little words, which we never used except in direst straits. She whistles, and you come running, like dogs.

‘It’s this.’

I shift Freya to my other arm, fish the envelope out of my pocket and push it across the table towards them.

It’s Fatima who picks it up, and her face is puzzled.

‘This is addressed to Kate. Wait –’ She slips a finger inside the ripped top, and checks inside, and her face pales as she looks up at me. ‘It’s not …?’

‘It’s not what?’ Thea twitches it out of her fingers, and then when she recognises the handwriting on the note inside her face changes. They are so unlike, so polar opposite in every way, rosy, bird-like little Fatima with her dark, watchful eyes and quick smile, and thin, sulky Thee, all bones and fags and heels. But their expressions, in that instant, are exactly the same – a mix of horror, shock and foreboding.

I could almost laugh at the similarity – if it weren’t for the fact that there is nothing, nothing funny about this situation at all.

‘Read it,’ I say, keeping my voice low, and as they pull the thin, fragile sheet out of the envelope and begin to scan down the page, I tell them, very quietly, about what Mary Wren told me. About the argument. I even tell them – my face flushing with defiant shame – about that night with me and Luc, and looking over his shoulder to find Kate there in the darkness, silently watching us both, her face a stone mask of horror.

I tell them about what it was that Ambrose found so sick and wrong. About Kate sleeping with Luc.

And finally I tell them about the bottle. About what Mark told Mary. About the heroin they have found in the bottle of wine.

‘An oral overdose?’ Fatima’s voice is a whisper, even though the bubble of the fryers drowns our conversation. ‘But, that makes no sense. It’s a stupid way to commit suicide, incredibly chancy – the dose would be really hard to calculate, and it’d take a long, long time. Plus it’s easily reversible with Naloxone. Why wouldn’t he just inject it? With his tolerance down, he’d be dead within minutes, with no chance of being revived.’

‘Read that note,’ I whisper back. ‘Read it from the perspective of a man who has just been poisoned by his child. Now do you see what I’m saying?’

I’m hoping against hope that they will tell me I’m being crazy, paranoid. That Kate would never hurt Ambrose. That being separated from the boy you love and being sent away is an absurd motive for murder.

But they don’t. They just stare at me, faces pale and frightened. And then Fatima manages to speak.

‘Yes,’ she says, and there’s a catch in her voice. ‘Yes. I see. Oh my God. What have we done?’

‘YOU GOING TO order something?’

We look up, all of us, at the man in the grease-stained apron standing with his hands on his hips at the end of the table.

‘Pardon?’ Thea says, in her best cut-glass accent.

‘I says –’ he enunciates his words with exaggerated care, as though for the hard of hearing – ‘are you ladies going to order any more food? Well over an hour, you’ve been sitting there taking up table space and she –’ he jerks his thumb at Fatima – ‘ain’t ordered so much as a cup of tea.’

‘Over an hour?’ Fatima jumps up, looks at her watch with horror, and then her shoulders slump. ‘Oh no, I can’t believe it. It’s quarter to nine. I’ve missed the train. Excuse me.’ She pushes past the man in the greasy apron. ‘I’m sorry, I’ve got to phone Ali.’

Outside the fish-shop window, she paces up and down, snatches of conversation filtering through the door as customers come and go. So sorry, I hear. Emergency … and really didn’t think it would take …

Thee and I gather up our things, and I strap Freya into her pram. Thea scoops up Fatima’s handbag along with her own, while I pick up the chips that Freya was playing with, gumming them mercilessly into pulp, before she threw them on the floor.

Outside Fatima is still talking.

‘I know. I’m so sorry, hon. Tell Ammi I’m sorry, and kiss the kids for me. Love you.’

She hangs up, her face twisted with disappointment.

‘Ugh, I’m such an idiot.’

‘You couldn’t go back, though,’ Thea says, and Fatima sighs.

‘I guess not. I suppose we’re really going to do this?’

‘Do what?’ I ask, but I know, before she answers, what she’s going to say.

‘We have to put this to Kate, don’t we? I mean, if we’re wrong –’

‘I bloody hope we are,’ Thea puts in grimly.

‘If we’re wrong,’ Fatima says again, ‘she has the right to defend herself. There could be a million ways to read that letter.’

I nod, but in truth I’m not sure there are a million ways. With Mary’s revelations fresh in my mind, the only way I can see it is a father trying to keep his child out of prison, knowing his own life is forfeit and doing the one thing he can do to keep her safe.