When she’d gone, there was silence. Mikey rinsed the fish under the running tap, laid it on the draining board, then washed his hands with warm water and soap. He used the scrubbing brush and took his time. Dex chopped herbs on a board. Warm midmorning light flooded through the window and splashed the floor.

‘She’s angry you didn’t tell her,’ Dex said after a while. ‘If you wanted a day off, you should have asked, that’s all.’

‘Something came up.’

‘It always does.’ Dex stopped chopping and looked at him. ‘You’re a clever boy, Mikey, and you could be a great chef. Don’t waste your talent.’

Mikey couldn’t help grinning as he dried his hands on a towel. Did Dex really believe in him that much? He wanted to please him suddenly, to make him think he was worth all the trouble.

‘I’ll finish the fish later if you like,’ he said.

Dex looked at the fish on the draining board, the entrails in the bin, the three fish still in the bucket.

‘A kind offer, but Sue has plenty to keep you busy, I think. I’ll finish these off and tomorrow I’ll show you how to make a stock out of the trimmings.’ He patted his belly. ‘I’ll teach you bouillabaisse – the best French soup you ever tasted.’

They shook hands on it and Mikey had something to look forward to again, just like that.

In the toilets he called Ellie again – still no joy, and no reply from his mum either. He risked phoning Karyn, figured it’d be worth getting yelled at if he found out what was happening.

She picked up straight away. ‘What do you want?’

‘Just wondered how it’s going?’

‘Fantastic.’

She sounded like she meant it, which was worrying. ‘Is Mum up?’

‘Yep.’

‘Can I speak to her?’

‘No.’

A stab in his guts. ‘Why, what’s she doing?’

He strained to hear background noises, something that would tell him Mum was simply in the kitchen, stumbling about making her first coffee of the day, that Karyn was bluffing, that this would still be all right. But he heard nothing, except the sound of his sister’s breathing.

‘Look,’ he said, ‘I’m sorry for everything, OK? Just tell me what’s happening.’

‘Why, so you can warn your girlfriend?’

‘I don’t want her to be scared, that’s all.’

‘You think I give a toss about that?’

‘She’s on your side, Karyn. If you want to hate someone, hate her brother.’

‘I hate them both.’

Everything tightened inside him as he pressed the phone closer, struggling to find a way to get through to her. ‘Ellie wanted to believe he was innocent – that’s not so weird, is it? If I did something terrible, wouldn’t you help me?’

‘You’d never do anything like that!’

‘That’s what she thought about him. He’s going to hate her for grassing him up, so why do you have to make it even more difficult? Why can’t you just tell me what’s going on?’

It felt like minutes waiting for her to speak. Eventually she said, ‘I’ll get Mum to call you when Gillian’s gone.’

And then she put the phone down.

Mikey rammed out of the toilets, through the bar, out of the main door and across the car park. He left Ellie a message as he walked: Call me. Serious. Call me as soon as you get this. He tried his mum, but she didn’t pick up. He tried Karyn again. Nothing.

He should have gone over to Ellie’s house after dropping Holly at school, he’d been an idiot not to. Or before school even – last night when it all kicked off. He could have climbed the gate, shinned up the drainpipe, spent the night by her side and kept her safe.

At the harbour wall he sat on a bench and tried to calm down. OK, it was possible Karyn was winding him up and his mum was still asleep. But it was also possible that Gillian was at the flat right now, finding out all the details, organizing squad cars. Couldn’t you be charged with perjury for lying to cops?

He left another message: I’m sorry, Ellie, I’m so sorry, but I think something bad’s about to happen.

Fourth apology in twenty‑four hours. He’d made such a cockup. He’d hurt Karyn, hurt Ellie, and he hadn’t meant to do either, not in a million years. He closed his eyes, tried to keep calm. If he just sat here, if he simply kept breathing, maybe it would be all right.

Thirty‑eight

Good girls aren’t supposed to think of a boy’s velvet neck, or the tilt of his head when he smiles. They’re especially not supposed to think of these things when it’s their last study skills session for the non‑calculator Maths exam.

Ellie blinked several times to erase all thoughts of Mikey.

‘So, that’s an example question,’ Ms Farish said. ‘Now please take up your notebooks, write down three criticisms of this method of estimation, and remember, as long as what you say is plausible and sensible, you should get the marks.’

Ellie sighed, and opened up her notebook. If she couldn’t concentrate on statistics and probability, she could at least do something useful. She turned to a blank page and wrote Revision, then she drew a table with twelve columns and divided up the weeks until the main GCSE exams began and gave the table thirty‑five rows. She’d revise for three hours every night when she got home from school. She’d eat dinner (half an hour), then she’d revise for a further two hours until bed. At weekends, she’d revise for ten hours a day and would reward herself with a DVD. She’d get seven hours’ sleep a night. She tried to work out how many total hours’ revision she’d given herself and how many hours’ sleep she’d get, but this was a non‑calculator study session and she couldn’t get her head round it. Instead, at the bottom of the page she drew a green snake with a red tongue.

Beyond the classroom window, sun glittered on the playground. The edge of the playing field was just visible and the grass looked very friendly waving at her. Ellie thought of the river, just out of view. She liked the fact she couldn’t see it, but that she knew its freezing sparkle would be making bright patterns on the fence.

The probability of something which is certain is one. The probability of something which is impossible is zero. Taking off her clothes and jumping into the river on that Wednesday afternoon when she should have been at school was definitely in the second category, and yet it had happened. How did mathematics explain that?

Statement: A girl and a boy jump into a river. The boy swims over to the girl and says, ‘God, it’s cold.’

Question: What’s the probability they will kiss?’

No, she mustn’t think of Mikey! She especially mustn’t think of kissing him yesterday – his kisses, soft and insubstantial at first, hardly there at all, and yet enough to make her blood leap. She mustn’t think of how the kisses built – becoming desperate, as if they were both searching for something.

She snapped her attention back to the classroom. Her plan was to work hard and make up for all the study sessions she’d missed, and there was no time in that regime for Mikey.

‘So,’ Ms Farish said, ‘let’s remind ourselves of different ways to represent data diagrammatically.’

Ellie wrote down, Horizontal axis, Vertical axis. She listened as Ms Farish described how to group data into classes. But when it came to drawing a graph, she drew a cottage instead, a fire, a boy, a zip. She wrote the words I’ve never felt this with anyone before. And bolded them, boxed them in. Wrote them again in capitals.

No one else seemed to be having trouble concentrating. She looked around at all the heads bent over tables, at all the pens feverishly scribbling. Statistically, there were kids in this room who cried themselves to sleep because of exams. They were exhausted, they had terrible headaches. They woke in the mornings feeling they’d had no sleep at all. Their eyes were itchy, their stomachs ached. These were her classmates, thirty of them, and she barely knew them at all.