Despite the protestations of the nurse they’d spoken with on their arrival at the hospital, the interview with Leah Cross was going ahead. It was impossible to feel any sympathy for the girl, though she continued with her vulnerable victim act with a professional precision.

‘There’s an unusually large amount of money in your bank account, Leah,’ Alex said, gesturing for Chloe to take a seat while she herself remained standing at the foot of the bed. ‘We assume you’ve got more stashed away in cash somewhere – you must have had something to live on over the past few days. Like to explain where that money came from?’

Leah looked from one woman to the other. She shrugged. ‘Savings.’

‘That’s quite a substantial amount of savings for a student,’ Chloe said. ‘Especially considering you don’t have a job.’

‘Not in the traditional sense,’ Alex added, her lip curling with the implication. ‘Amy Barker has identified you as the person who sold her the drugs. The street outside the club has plenty of CCTV, so it’s only a matter of time before we find one that picked you up there that night.’ This was a lie. The CCTV from the club had been scrutinised; Leah was nowhere to be seen. The girl obviously knew where the cameras were. ‘Tom Stoddard claimed you were involved in dealing drugs. You know what’s happened to him, don’t you, Leah?’

Leah turned her head towards Alex, her face masked with a look of feigned ignorance. God, she was good, Alex thought.

‘What do you mean?’

‘Tom’s been killed.’

She held the detective’s gaze, putting on her best show of surprise. She even managed to force tears to her eyes. How much practice had she had at all this pretence?

‘Seems convenient for you that he’s no longer able to incriminate you.’

‘What happened to him?’ Leah said, the question asked out of duty rather than concern.

‘He was stabbed. Probably best you start telling us the truth, don’t you think?’

The girl turned away and looked out of the window at the blank square of sky that stretched into the distance. ‘I’ve been stabbed too,’ she said flatly. ‘I’m the victim here.’

Chloe shot Alex a look, rolling her eyes at the girl’s self-pity. It seemed that Leah Cross and Tom Stoddard had been two of a kind: both careless to anyone else’s suffering.

‘You went back to the house,’ Chloe said. ‘Your mobile phone was there. Did you see Tom while you were there?’

Leah shook her head. Chloe and Alex exchanged another look; they were never going to get the truth from this girl.

‘Isobel Matthews has been discharged,’ Alex told her, ‘but she’s still in quite a state. Her face is black and blue, she’s got a broken nose and two cracked ribs. I’m finding it difficult to believe you were able to inflict that level of injury after receiving a stab wound to the stomach, on top of the injuries you’d already sustained in the hit-and-run.’

‘Believe what you want,’ Leah said flippantly.

‘I’ll tell you what I believe. I believe that Isobel wanted to stab you and had every intention of doing so, but you managed to overpower her. She didn’t get a chance to hurt you, did she? I believe you attacked her first and then stabbed yourself in an attempt to make Isobel’s injuries look like self-defence.’

Leah said nothing, her face still turned to the window.

‘Assault, blackmail, drug dealing … not looking good for you, is it?’

Alex crossed the room and stood in front of the window, blocking Leah’s view of the outside world. The girl looked away, determined not to make eye contact.

‘We know all about the money Leighton Matthews was transferring to your bank account, Leah. He’s told us everything. His daughter and his wife are still under the impression the two of you were having an affair. Don’t you think it’s time they knew the truth?’

‘I’ve told the truth.’

Alex wondered whether part of Leah believed that. Had her lies spread so wide – had her story become so elaborate – that she’d started to live the life of the person she pretended to be rather than the one she was? Had she told so many lies she’d come to forget what the truth was?

‘I’ve spoken to your mother.’

For the first time, Leah looked directly at Alex. Her face was set in a grimace; her eyes questioning whether Alex was telling the truth.

‘Your real mother,’ Alex added. ‘Not Carol Brooks … Carol Chambers … whichever you prefer to refer to her by.’

Leah looked to Chloe as though for sympathy or support, but it was evident she wasn’t going to get either. She slid further beneath the hospital blanket, wincing at the pain caused by the movement.

‘You’re not going to ask how she is?’

‘No.’

‘OK.’ Alex folded her arms across her chest and stepped away from the window. ‘It’s quite a story I heard this morning, Leah. Troubled young girl having difficulties at home, arguing with her mother; mother can’t cope, despite her best efforts, so someone else steps in, the parents of one of the girl’s friends. They offer to let the girl stay with them for a while, so she and her mother can resolve their differences. Very kind of them, don’t you think? Unusually generous. You’d think the girl would be grateful that someone else cared enough to do something like that for her. But not this girl. This girl takes and takes until they’ve nothing left to give.’

Leah was crying. They were silent tears, fat and steady on her paled cheeks.

‘Keira was your friend, wasn’t she?’

Leah ran a hand over her face before turning to Alex. ‘Of course she was my friend,’ she snapped.

‘Must be difficult for you now,’ Alex said, ‘knowing your lies might have killed her.’

A guttural sob escaped Leah’s chest. She shook her head, trying to deny the words.

‘Carol’s daughter Kirsty was your friend too, wasn’t she?’

The mention of the girl’s name was enough to confirm Leah’s guilt: a guilt that stamped itself upon her face with the force of a slap. She shifted beneath the sheet and winced again, turning her head to the side in an attempt to hide her tears.

‘She trusted you with her secrets like a sister would and you listened like a good friend, storing away all the details. She had no idea you were going to use them for your own gain, did she?’

Leah was shaking her head. ‘You think you get it,’ she said, ‘but you don’t understand anything. You should be talking to Isobel, not me. She hit me with Leighton’s car. She’s the one in the wrong here, not me.’

‘Telling yourself that must make everything so much easier,’ Chloe said.

Leah shot her a glance of contempt. ‘Look at you,’ she said with a sneer. ‘Just like the rest of them. Spoilt little rich girls. Why haven’t you arrested Isobel? Because she looks better than I do. Because she has more money and her family is more respectable. She talks better than I do, so she can’t possibly be bad, can she? She’s going to walk away from all this because you lot are too stupid to get anything right. And I’ll get the blame, just like always.’

‘Is that what this is all about?’ Alex asked. ‘Money? Is that why you resented Kirsty – why you thought it would be acceptable to use her past to line your own pockets? Is that why you befriended Keira? I don’t think either girl was really your friend, Leah. I think you used them for what you could get, and when you were done with them you ditched them. Other people are just a means to an end to you, aren’t they?’

Leah pressed her face against the pillow. ‘You can keep talking if you want, but I’m done now.’

‘There was only one more thing anyway,’ Alex said. ‘Leah Cross, I’m arresting you for the supply of a class A substance. You do not have to say anything …’

As she read Leah her rights, Alex returned to stand at the foot of the bed. The girl’s silent tears had returned, absorbed into the stiff cotton of the hospital pillowcase. Alex didn’t believe for a moment that any of the tears she shed were for the people she had caused harm: for Kirsty Brooks, whose past she had stolen; for Amy Barker, whose life been jeopardised; for Keira, whose life had been taken. Leah Cross’s tears were for herself.