Dan, Chloe and Alex sat in Alex’s office discussing the morning’s events. As requested, Dan had been to visit Melissa Matthews, but the woman’s story had remained the same: Leighton had been out the evening Leah had been hit by his car and had come home during the early hours of the following morning. ‘She’s not shifting,’ he told them. ‘It was like getting blood from a stone.’

‘She’s protecting Isobel,’ Alex said. She ran a hand through her hair, pushing it back from her face. ‘Unless we get something concrete against her, Isobel Matthews is going to walk out of here.’

She sat back in her chair and tilted her face to the ceiling, focusing on the glare of the strip light above. Leah Cross was also likely to walk free, despite the fact that she’d been arrested for supplying the drugs that had landed Amy Barker in hospital. All they had was Amy’s statement and the claims Tom had made during his interview, with nothing substantial to support either. They couldn’t afford to have anyone else escape justice.

Isobel Matthews was downstairs in one of the interview rooms with a duty solicitor. So far, she had said little. She seemed to know exactly what to do. Presumably she’d already been briefed by her father and was now getting a second helping from the lawyer.

‘How are we getting on with the other people from the party? Any updates?’

Dan shook his head. ‘A few people have been spoken to, but no one remembers seeing Isobel there. There are quite a lot more still to get through.’

Alex admired Dan’s optimism, but she couldn’t share it. An ID on Isobel Matthews wouldn’t be enough to secure a conviction against her; it would be laughed out of the courtroom. At this rate, they were going to look incompetent at best.

‘Isobel wouldn’t have needed to be at the party that long,’ Chloe said, echoing Alex’s concerns. ‘She only needed to look for Keira – or Leah, as she thought she was – and if she acted on impulse like you think,’ she looked at Alex, ‘the whole thing would have been over in moments. The panic was coming from outside by then – that’s where everyone’s attention would have been. Isobel just needed to slip back downstairs and out through the front door and she was gone.’

‘How did she know where to find her, though?’ Dan asked. ‘Upstairs on the top floor doesn’t seem the most obvious place to start.’

‘Seems too much of a coincidence that she just chanced on her there,’ Chloe agreed.

They sat in silence for a moment, puzzling over the possibilities.

‘She asked someone,’ Alex said. ‘It’s the only thing that makes sense. She asked someone where Leah was and someone pointed her in the direction of upstairs.’

‘But Leah was in the garden,’ Chloe said, blowing the theory apart. ‘According to all the housemates’ statements, that’s where she’d been for most of the night.’

‘True.’ Alex stood and gestured to Chloe. ‘Come on … let’s find out what she’s got to say for herself.’

---

Despite her injuries and the events of the past forty-eight hours, Isobel Matthews had found the time and energy to go home, change her clothes and apply make-up. It wasn’t enough to conceal the vivid bruising that marked her face and hung in heavy shadows beneath her eyes; if anything, it seemed to draw greater attention to it.

‘Could you confirm for the recording that your name is Isobel Matthews; address Flat 24b, Waterview Apartments, Cardiff Bay.’

‘Yes.’

‘Tell us about what happened at the house on Broadway, please, Miss Matthews.’

‘I already told you,’ Isobel said. ‘I met Leah there. I knew she’d come because she’d think it was my father.’

‘Why did you want to meet her?’

‘That girl has been sleeping with my father,’ Isobel said angrily, a flare of red erupting behind the bruising on her cheeks.

‘So you were angry with her?’ Alex asked. ‘You wanted to confront her about it? You weren’t angry with your father too?’

Isobel’s jaw tensed. ‘I hate him. Everything he’s put us through.’ She stopped for a moment and sat back in her seat.

‘You told us that Leah attacked you.’

Isobel nodded. ‘She went crazy, like some wild animal. She just lost it. And then she stabbed herself in the stomach.’ She looked to the duty solicitor in disbelief. ‘She had the knife in her hand and I thought she was going to attack me with it. Instead, she just stabbed herself. She’s a lunatic.’

‘How did you find out there was something going on between your father and Leah Cross?’

Isobel hesitated, choosing her words carefully. ‘You arrested him for hitting her with his car,’ she said, as though they needed reminding of this. ‘It didn’t take much working out, not with his track record.’

Alex studied Isobel’s face, searching for visual indications of her lies. The girl had gone out that evening knowing exactly what she intended to do. She had wanted to hurt Leah, and she had wanted her father to take the blame. Leighton had needed to suffer for everything he had done to his family.

‘I think you knew about it before then. Quite a while before then.’

Isobel said nothing.

‘Leah was blackmailing your father,’ Alex told her. ‘You probably already knew that too. How did you find out?’

The girl faced Alex defiantly, but again refused to speak.

‘Here’s what I think,’ Alex said. ‘I think you found evidence of Leah’s blackmail – a bank statement, perhaps, or an overheard conversation – and you put two and two together. I think you’ve probably been looking for a while for evidence of another affair. You and your mother have had quite a lot to put up with over the past few years.’

The girl had clammed up now, seeming to realise that anything further she might say could incriminate her. She wore the same resilient look they’d seen stamped on the face of her mother: a calm, determined expression that implied a resolve not to be caught off balance. Where Melissa Matthews was concerned, that resilience appeared to apply to her marriage. It seemed that until now – until her daughter had become involved in such an incriminating way – Melissa had been willing to accept her husband’s behaviour, facing each affair with the same headstrong defiance with which she dealt with everything else.

Isobel’s resilience told a different story. For her, this seemed a chance for revenge. Her father had made the family suffer. Now she was going to repay the favour. With no evidence against her, everything pointed towards him. She was clearly hoping he would be arrested and charged with the hit-and-run. She must have known that neither of her parents would correct the police in their assumption that it had been Leighton who was responsible.

‘Do you go to your father’s office regularly?’ Alex asked.

Across the table, Isobel’s eyes narrowed. ‘Why are you asking that?’

‘We know that Keira North delivered an essay there for Leah Cross. That essay never made it to Leighton – he claims never to have seen it.’

‘Perhaps he’s lying,’ Isobel said. ‘He makes quite a habit of it, haven’t you noticed? I don’t see what relevance this essay has to anything anyway.’

‘Do you want to tell us what you did with it?’

Isobel looked at her lap. ‘I don’t know what you’re talking about.’

‘I think you do,’ Alex said. ‘I think you were there that day, at Leighton’s office. Keira wrote an email to your father telling him she’d left the essay on his desk. In that email, she mentioned having spoken briefly with a member of staff there, someone who told her it was fine for her to leave it there. I think that was you. You’d already found out by this point that your father had some sort of involvement with a woman called Leah Cross. You picked up that essay, saw the name, and made the mistake of assuming Keira was Leah.’

Alex sat back for a moment, continuing to study Isobel. The girl’s resilience was still firmly stamped in place.

‘You probably checked out her Facebook page,’ Alex continued. ‘You wouldn’t have seen much – Leah’s account is set to private. But her profile picture is a photograph of her and Keira together.’

Still Isobel said nothing.

‘You went to that party with the intention of confronting the girl you thought was Leah Cross about her relationship with your father. What did you hope to do, Isobel? Humiliate her in front of her friends? Or did you set out with the intention of hurting her?’ Alex paused, waited a moment, but the young woman’s silence was defiant. ‘You found her sitting upstairs on the ledge outside her bedroom window. Did she see you come in? Or was her back turned to you, unsuspecting?’

‘This is a very elaborate theory, DI King,’ the duty solicitor said, ‘but have you proof of any of it?’

‘I think you reacted impulsively,’ Alex continued, ignoring the solicitor. ‘All the anger you felt at your father and his behaviour over the years was released for a moment when you pushed her. You went away thinking that some sort of justice had been served. But what then? You saw Keira on the news, realised she wasn’t Leah – that you’d made a mistake. You found out she’d been pregnant. Did you feel guilty when you realised what you’d done? Or did it cause a whole wave of fresh anger? It was Leah’s fault that Keira died. She needed to pay for it, didn’t she?’

Isobel Matthews still refused to respond, but the truth was there. It was in her eyes; in the glazed, watery mist that had filled them and that she now fought back, almost concealing it behind the defiance she wore so well.

Leah Cross and Isobel Matthews might have led very different lives, Alex thought, but in many ways the two girls were so similar. It seemed almost ironic now that they weren’t related after all.

‘Interview paused at 14.37,’ she said, reaching across and stopping the tape recorder. ‘You might be interested to know,’ she added, standing from her chair, ‘that Leah has never been involved with your father. Not in the way you thought. So all this has been for nothing.’