Later that morning, Alex and Chloe pulled up outside the semi-detached house in Llandaff that belonged to Leighton Matthews and his wife. This was an affluent area of Cardiff, characterised by large houses and sprawling gardens. The wide driveway housed a Mini convertible, but the first thing both women noticed was the absence of a 4x4.

‘Nice,’ Chloe said, gesturing to the house. ‘Didn’t think lecturers were paid that well.’

‘Wife does all right for herself, by the looks of things. Owns three salons.’

‘Maybe I could get my roots done while we’re here.’ Chloe stepped from the car. She was tired after the previous evening’s restless night, but the make-up she’d applied carefully that morning was doing a good job of concealing the telltale signs of her need for sleep. It had been worth staying awake to get Alex to finally talk.

They walked up the driveway and rang the bell. Moments later, Leighton Matthews answered. He was tall and athletic in frame, quite different from the suggestions offered by the photographs Chloe and Alex had seen of him online. He was wearing fashionable clothes that seemed to Chloe slightly out of place on a man of his age, although even as the thought occurred to her she wondered what he was supposed to be wearing now he was in his forties, as if hitting a certain decade meant a life committed to sensible shoes and corduroy trousers. ‘Detective Inspector Alex King.’ Alex introduced herself. ‘This is Detective Constable Chloe Lane. Do you have a few minutes?’

Leighton Matthews didn’t move from the doorway, seemingly reluctant to let them into the house. ‘Now? I mean … I’m a bit busy at the moment.’

‘With what?’ Alex asked. ‘Term’s over, isn’t it?’

Matthews looked unsettled by the comment, disconcerted by the fact that they knew enough about him to know what his job was. ‘What’s this about?’

‘We’re investigating a hit-and-run that took place the night before last. We’re just talking to people to eliminate them from enquiries.’ Alex glanced to the fence that divided Leighton’s driveway from the one next door. The neighbour was at his recycling bin, the lid held half open as he stood listening to the conversation taking place on the other side of the fence. She nodded an acknowledgement before turning back to Matthews. ‘We can continue out here if you like, or perhaps you’d prefer a bit of privacy.’

Matthews stepped back reluctantly to allow them to enter the house. Inside, the property was something taken straight from the pages of an interior design magazine. Everything was in neutral colours, from the white walls to the pale grey furniture. The decor was sparse, and light poured into the hallway from a huge window at the top of the wide staircase. The place looked barely lived in – a show home – and the air smelled of plug-in fragrances, so strong it caught Chloe in the back of the throat.

They followed Leighton Matthews through to the kitchen, where a teenage girl wearing a tiny pair of pyjama shorts and a vest top was standing waiting for the kettle to boil. She threw the two detectives a glance, her eyes lingering on Chloe’s outfit for a moment, before turning her attention back to tea-making.

‘My daughter,’ Matthews said, though the girl hadn’t acknowledged him. ‘Younger.’

The girl left the room, eyeing the two women with suspicion before heading upstairs with her cup of tea. Matthews returned to where he’d obviously been working at the table. His laptop was open beside a pile of paperwork.

‘Next book?’ Chloe asked.

He looked at her in surprise. ‘Yes. I mean … it’s just notes at the moment, but hopefully.’

Once again, he seemed disconcerted at the fact that they already seemed to know so much about him.

‘What do you write?’

‘Literary fiction.’

Chloe raised her eyebrows, but said nothing. She wondered whether a proficiency for writing fiction made someone a good liar.

‘Look,’ he said, folding his arms across his chest. ‘I don’t really know why you’re here. I don’t know anything about a hit-and-run.’

‘Do you know Leah Cross?’ Alex asked.

His reaction made the answer clear. At the mention of the girl’s name, he flinched. ‘She’s a student at the university. Why?’

‘She was hit by a car on Wednesday night.’

He was silent for a moment, avoiding eye contact with either woman. ‘Oh. Well … I’m sorry to hear that.’ He pointlessly pushed a pile of paperwork to one side. ‘Is she OK?’ he asked, his face turned from them.

‘She’ll live,’ Alex told him. ‘Could you tell us where you were on Wednesday night, Mr Matthews? Between the hours of eleven p.m. and one a.m.’

‘I was here,’ Matthews said without hesitation. ‘In bed.’

‘Was your wife home?’

‘Yes.’

Alex nodded, taking in the details of the expensive kitchen: huge American-style fridge, chrome fittings, bi-folding doors that looked out on to an expanse of neatly tended back garden. ‘The thing is, Mr Matthews,’ she said, taking a seat at the table, ‘a car of the same make and colour as yours was seen leaving the scene of the incident on Wednesday night.’

‘There are hundreds of cars like mine on the roads. Thousands, probably.’

‘We have an eyewitness. The number plate is a close match with yours.’

‘A close match. So not exact, then?’

‘Where is your car, Mr Matthews?’ Chloe asked.

Matthews hesitated. ‘It’s in the garage.’

‘Your garage here at the house, or do you mean another garage?’

He looked from Chloe to Alex. ‘It’s cut out on me a few times over the past couple of weeks. I took it in to have it checked over.’

‘When did you take it in?’ Alex asked.

‘Yesterday.’

‘Right,’ she said. She shot Chloe a look. Leighton Matthews had taken his car to a garage the morning after the hit-and-run. They needed to get their hands on it before further evidence was lost, if it wasn’t already too late for that. ‘And the name of the garage?’

‘Lockley’s down on Western Avenue. Look …’ Matthews glanced at the huge clock that hung on the wall above the sink. ‘Is there anything else? I really am very busy.’

Alex sat back, making it clear she was in no hurry to leave. ‘You don’t seem too concerned about the welfare of your student, Mr Matthews.’

He leaned on the back of the chair that faced her. ‘You said she’s OK.’

‘How well do you know Leah Cross?’

Matthews exhaled. ‘As well as I know any of the students. She comes to my lectures, she writes me essays, I mark them and hand them back. I don’t know any of them particularly well.’

‘What about Siobhan O’Leary?’ Chloe asked. ‘Did you know her well?’

His face fell for a moment. It wasn’t long before the look of surprise morphed into an expression of anger. His fists gripped the back of the chair in front of him. ‘I said everything there was to say about that at the time. There were no charges brought against me and the reason for that was because she was lying. There was something wrong with that girl, everyone knew it.’

‘Something wrong with her?’

‘Delusional. Obsessive. There was no truth in any of her claims. Now … are we done here?’

Alex stood. ‘That’ll depend on your car, won’t it?’ She was interrupted by the sound of her mobile phone. ‘DI King,’ she said, heading out into the hallway as she took the call. There was a lengthy pause. ‘OK … we’re on our way.’ She came back into the kitchen. ‘We’ll be in touch, Mr Matthews,’ she said, nodding Chloe from the room.

‘Everything OK?’ Chloe asked as the door to the Matthews house was closed behind them.

‘Tom Stoddard. He’s been murdered.’