Issy found the worries and cares of the café, which had lain on her relentlessly for months, it felt, somehow get soothed away in the strange underwater tranquillity, as Austin made her laugh with stories about Darny at school or touched on, without a trace of self-pity, how hard it was to be a single parent who wasn’t even a parent. And in return, Issy found herself talking about her own mother – normally when she spoke of her family, she talked about how amazing her grandfather was, and how they’d all lived together, and made it sound cosy. But talking to someone who knew how it felt to lose a parent, absolutely and irrevocably, made it easier somehow to talk about how her mother had danced in and out of her life, trying to make herself happy but not succeeding in making anyone happy.

‘Were your parents happy?’ she asked.

Austin thought about it. ‘You know, I never considered it. Your parents are just your parents, aren’t they? It never even occurs to you till you grow up, whatever they’re like, that they aren’t completely normal. But yes, I think they were. I used to see them touch all the time, and they were close, always physically close, holding hands, close to one another on the sofa.’

Without thinking, Issy glanced down at her own hand. It was silhouetted in front of a gently glowing tank filled with darting eels, not far from Austin’s. It crossed her mind: how would it feel if she was to take his hand then and there? Would he pull away? She could almost feel her fingers tingle in anticipation.

‘And of course, there was the fact of them being completely and utterly ancient and having another baby when all their friends were becoming grandparents. So, you know, something must have gone all right. Of course at the time I thought it was totally disgusting …’

Issy smiled. ‘I bet you didn’t really. I bet you loved him from the get go.’

Austin glanced over at Darny, whose eyes were wide; his gaze following the shark around its tank, completely hypnotized.

‘Of course I did,’ mumbled Austin, and turned away slightly, his hand moving further from Issy’s, who felt embarrassed suddenly, like she’d gone a little too far.

‘I’m sorry,’ she said. ‘I didn’t mean to be so personal.’

‘It’s not that,’ said Austin, his voice a little muffled. ‘It’s just … I would have liked to know them, you know? As a grown-up, not an overgrown teenager.’

‘You’re making me want to go phone my mum,’ said Issy.

‘You should,’ said Austin.

Now it was Issy’s turn to glance away.

‘She’s changed her number,’ she said quietly.

And almost without realizing he was doing it, Austin put out his hand to take hers, at first in a gentle squeeze, but then suddenly he didn’t want to put it down.

‘Ice cream!’ came a very loud voice from below them. Immediately they dropped each other’s hand. It was too dark down here, Issy found herself thinking. Like a nightclub.

‘I spoke to the shark,’ said Darny importantly to his brother. ‘He said that I would make a very good marine biologist and also that it would be OK for me to have some ice cream now. In fact he thought it was quite important. That I got some ice cream. Now.’

Austin looked at Issy, trying to read her face, but it was impossible in the gloom. It was very awkward, all of a sudden.

‘Um, ice cream?’ he said.

‘Yes please!’ said Issy.

The three of them sat by the river, watching the boats go by and the great wheel of the London Eye overhead, and were still enjoying each other’s company, so much so in fact that Issy hardly noticed the time. When Darny finally came off the high climbing frame and grabbed Issy’s hand with his sticky paw as they left the park, she didn’t mind a bit – was pleased in fact (Austin was stupefied) – and they decided as a special treat to take a cab back to Stoke Newington, whereupon Darny, having attempted to press all the buttons, curled up in the back and fell asleep on Issy’s shoulder. When Austin glanced over two minutes later as the cab trudged slowly through the traffic, he saw Issy, too, fast asleep, her black curls tangled with Darny’s spikes, her cheeks pink. He stared at her all the way home.

Issy couldn’t believe she’d fallen asleep in the cab. OK, she’d had no rest the night before, but still. Had she dribbled? Had she snored? Oh God, horrific. Austin had just smiled politely and said goodbye … Oh God, that meant she must have then, because surely otherwise … wouldn’t he have asked for another date? Although that wasn’t a date, was it? Was it? No. Yes. No. She thought again of the moment when he’d held her hand. She couldn’t believe how much she’d wanted him to go on holding it. Putting her key in the door, Issy moaned. Helena would know what to do.

She caught sight of herself in the filigree mirror that hung in the tiny hallway, over the flower-sprigged retro wallpaper she was so proud of. She hadn’t realized till then that she must have had that big white streak of wedding-cake flour in her hair all day.

‘Helena?! Lena! I need you,’ she bawled, stalking into the sitting room and marching over to the fridge, where she knew they had a couple of bottles of rosé left over from something. Then she stopped, and turned round. There on the sofa, sure enough, was Helena. And beside her on the sofa, someone she thought she recognized. They were in the exact positions of people who’d suddenly jumped apart in an effort to look completely innocent of any wrongdoing.

‘Oh!’ she said.

‘Hello!’ said Helena. Issy looked at her carefully. Could she … ? She couldn’t possibly. Could she be blushing?

Ashok was pleased. Meeting Helena’s friends was definitely a good step forward. He jumped up immediately.

‘Hello, Isabel. How lovely to see you again,’ he said politely, shaking her hand. ‘I’m—’

‘Ashok. Yes, I know,’ she said. He was much handsomer than she’d remembered, out of his rookie-looking short white coat. Over the top of his head she waggled her eyebrows furiously at Helena, who was pretending to ignore her.

‘So what is it you need to ask me?’ said Helena, trying to change the subject.

‘Um, not to worry,’ said Issy, moving over to the fridge. ‘Who’d like some wine?’

‘Your gramps called,’ said Helena, when they were all ensconced in the sitting room. Ashok made for very easy company, Issy noted, pouring wine and adding comments when needed.