Fiona also noticed a couple of older people smile at her, and something else too. Often, when she went out, she would catch young men giving her the eye. A blonde woman with a nice figure and a pretty face. Of course they did. But when she was with Rose she became invisible to these men. Some of them might be into MILFs in their fantasies, but in real life they just saw a mum. No longer a sexual object. She realised that, in the eyes of society, she appeared to have a new identity. A mother. A harmless mum out with her child.

Half the world wouldn’t even notice her. And the other half certainly wouldn’t suspect her of anything bad.

That included the grotesque man beside her now, who was still scratching when they pulled into Victoria. The moment the train juddered to a halt, Fiona stood up and trod on the scrofulous dickhead’s foot, stamping her Doc Marten down on his soft trainers.

He cried out.

‘Oh, I’msosorry,’ she said. ‘Are you okay?’

She wanted to tell him he was lucky they weren’t alone in the carriage – or on a dark platform, late at night, nobody around, a train heading into the station. All it would take was a nudge, followed by flailing limbs, a cry of alarm drowned out by the rush of the train. She could see it. Feel the heat in her bones as she pictured it; pulse accelerating, blood thickening, the hairs on the back of her neck standing on end.

‘Come on, Rose,’ she said, studying the girl’s face for signs, but Rose’s face remained neutral. Watchful. ‘This is us.’

They changed on to a train to Herne Hill and turned right out of the station. Fiona took a baseball cap out of her bag and slipped it on, tucking her ponytail through the gap at the back and pulling the peak low. It might have been four years but there would still be people around here who knew her. Who remembered what she had done.

They passed the pub where she and Maisie had spent many hours at the pool table, beating anyone foolish enough to take them on, then turned on to a side street which was lined with tall trees. Beneath one of these trees was a bench. They sat down.

‘What are we doing?’ Rose asked, looking all around.

‘Before I tell you, let me ask you something. When you heard that Albie had been hurt in that accident, how did it make you feel?’

Rose blinked at her. ‘I don’t know.’

‘Come on. You can be honest with me. Do you want to know howIfelt?’ Fiona glanced around, then put her face close to Rose’s. Conspiratorial. ‘I thoughtserves him right.’ Rose’s eyes widened. ‘Serves him right for being so mean to you, and for getting his dogs to scare poor Lola. He was rude to me too. Insulting. So no, I don’t feel sorry for him.’

She waited for Rose’s response. She appeared to be thinking hard. Eventually she said, ‘My dad says we shouldn’t wish harm on anyone. He says that kids who are bullies or mean probably have bad home lives and that we should feel sorry for them. Try to understand them.’

‘Hmm.’ The very definition of a bleeding-heart liberal. ‘And what do you think, Rose? I promise this isn’t a trap. I’m not going to snitch. I just want to understand how you feel. Does Rose Dove agree with her dad?’

‘It’s wrong to be glad that someone else is suffering.’

‘Is that another quote from your dad? It’s okay. I’m not going to argue with you. You probably think I’m a bad person for saying I think it served him right. But do you know what else I think, Rose? Something that’s even more important. I think you shouldn’t fight your feelings.’ She laid a hand on her own belly. ‘Right here, in your gut, that’s where the truth lies. I let that guide me. Put your hand on your belly, Rose.’

Rose obeyed.

‘What’syourgut telling you right now?’

‘That I’m hungry.’

Fiona laughed. ‘Okay. I promised you an ice cream, didn’t I? We can—’

She fell quiet because the front door of the house they were sitting diagonally opposite was opening. It was him. Max. Fionaimmediately put her hand in front of her face to shield it, but he was too busy staring at his phone to look over. He began to shuffle up the street away from them, thumbing his phone as he went.

Hurriedly, Fiona said, ‘We can go to the café in the park in a little bit. But first, I’m going to tell you a little secret.’

Rose’s eyebrows went up. ‘A secret?’

‘We’re not really here to study architecture. That’s boring. Houses are houses, right? I’m actually going to teach you something far more useful. We’re going to study spycraft. Doesthatsound exciting?’

‘Spycraft? Like, what, pretend we’re spies?’ Rose was looking at her like her bullshit detector was flashing red and beeping. ‘Are you for real?’

‘One hundred per cent. And we’re going to start now. We’re going to follow that man.’

Max was already heading away from them down the street, still ambling along, not watching where he was going. Fiona noted that he was wearing a smart shirt and suit jacket on top, but scruffy jeans and trainers on his bottom half. What was that all about? And why was he at home on a Tuesday morning?

She got up from the bench and gestured for Rose to do likewise.

‘It’s important that he doesn’t see us,’ Fiona said. ‘But I don’t want to lose track of him. Okay? So we follow, but keep back. If he sees us, we fail. Got it?’