Like many officers, Holland had not yet got used to the fact that SO units had officially been renamed SCD units, now that they were part of what had become known as the Specialist Crime Directorate. Most people still used the old abbreviations, knowing full well that the brass would change the name again soon enough, next time they were short of something to do. SO7 was the Specialist Operations department whose component command units dealt with everything from contract killings to serious drug crime. Aside from the Kidnap Unit, these OCUs included the Flying Squad, the Hostage and Extortion Team, and the Projects Team, with whom Thorne had worked on the joint gangland operation that had ended so badly the previous year.

‘Not the Kidnap Unit, mercifully. They’re high-flyers; they don’t like to mingle with the likes of us. They like to stay a bit mysterious.’

‘Well, I suppose there has to be an element of secrecy, bearing in mind what they do. They have to be a bit more discreet than the rest of us.’

Thorne looked unconvinced. ‘They fancy themselves.’ He leaned across and turned on the radio, tuned it in to Talk Sport.

‘So this bloke Mullen knows Jesmond, does he?’

‘Known him for years.’

‘Same sort of age, then?’

‘I think Mullen’s a few years older,’ Thorne said. ‘They worked together on an old AMIP unit south of the river somewhere. The DCI reckons Mullen was the one responsible for bringing Jesmond on. Pulled our Trevor up through the ranks.’

‘Right…’

‘Remind me to punch the fucker, would you?’

Holland smiled, but looked uncomfortable.

‘What?’

‘Someone’s kidnapped his son…’ Holland said.

On the final stretch of the Edgware Road, approaching Marble Arch, the traffic began to snarl up. Thorne grew increasingly frustrated, thinking that if the congestion charge had made a difference, it was only to people’s wallets. On the radio, they were talking about the game Spurs were due to play the following evening. The studio expert said they were favourites to take three points off Fulham, after three wins on the bounce.

‘That’s the kiss of bloody death,’ Thorne said.

Holland was clearly still thinking about what had been said a few minutes earlier. ‘I think you just see these things differently,’ he said. ‘Once you’ve got kids, you know?’

Thorne grunted.

‘If something happens to somebody else’s-’

‘You think I was being insensitive?’ Thorne asked. ‘What I said.’

‘Just a bit.’

‘If I was really being insensitive, I’d say it was divine retribution.’ He glanced across and raised an eyebrow. This time, the smile he received in return was genuine, but it still seemed to sit less easily on Holland’s face than Thorne might once have expected.

Holland had never been quite as fresh-faced, as green and keen, as Thorne remembered; but when he’d been drafted on to Thorne’s team six years before as a twenty-five-year-old DC, there had certainly been a little more enthusiasm. And there had been belief. Of course, he and his girlfriend had been through domestic upheavals since then: there’d been the affair with a fellow officer who’d later been murdered on duty; then the birth of his daughter, who would be two years old later in the year.

And there’d been a good many bodies.

An ever-expanding gallery of those you only ever got to know once their lives had been taken from them. People whose darkest intimacies might be revealed to you, but whose voices you would never hear, whose thoughts you could never be privy to. An exhibition of the dead, running alongside another of the murderous living. And of those left behind; the pickers-up of lives.

Thorne and Holland, and others who came into contact with such things, were not defined by violence and grief. They did not walk and wake with it, but neither were they immune. It changed everything, eventually.

The belief became blunted…

‘How’s everything at home, Dave?’

For a second or two, Holland looked surprised, then pleased, before he closed up, just a little. ‘It’s good.’

‘Chloe must be getting big.’

Holland nodded, relaxing. ‘She’s changing every five minutes. Discovering stuff, you know? Doing something different every time I get home. She’s really into music at the moment, singing along with whatever’s on.’

‘Nothing with twangy guitars, though.’

‘I keep thinking I’m missing it all. Doing this…’

Thorne guessed there was little point in asking about Holland’s girlfriend. Sophie was not exactly Thorne’s greatest fan. He knew very well that his name was far more likely to be shouted than spoken in the small flat Holland and Sophie shared in Elephant & Castle; that he might well have caused a fair number of the arguments in the first place.

The BMW finally hit thirty again on Park Lane. From here, they would continue down to Victoria, then cut across to St James’s and the Yard.

Holland turned to Thorne as they slowed at Hyde Park Corner. ‘Oh, by the way, Sophie told me to say “hello”,’ he said.

Thorne nodded, and nosed the car into the stream of traffic that was rushing around the roundabout.

This was not his favourite place.

It was here that he’d spent a few hideous weeks the year before; perhaps the most miserable he’d ever endured. Back then, when he’d been taken off the team, and given what was euphemistically called ‘gardening leave’, Thorne had known very well that he wasn’t being himself, that he hadn’t been coping since the death of his father. But hearing it from the likes of Trevor Jesmond had been something else; being told he was ‘dead wood’ and casually wafted away like a bad smell. It was the undercover job that had thankfully provided a means of escape, and the subsequent weeks spent sleeping on the streets had been infinitely preferable to those he’d spent stewing in a windowless cupboard at New Scotland Yard.

As they walked towards the entrance, Thorne scowled at a group of tourists taking photographs of each other in front of the famous revolving sign.

‘What did you do when you were here?’ Holland asked.

Thorne took out his warrant card and showed it to one of the officers on duty at the door. ‘I tried to work out how many bottles would constitute a fatal dose of Tippex…’

Kidnapping and Specialist Investigations was one of a number of SO units based in Central 3000, a huge, open-plan office that took up half of the fifth floor. Each unit’s area was colour-coded, its territory marked out by a rectangular flag suspended from the low ceiling: the Tactical Firearms Unit was black; the Surveillance Unit was green; the Kidnap Unit was red. Elsewhere, other colours indicated the presence of the Technical Support and Intelligence units, either of which could make use of an enormous bank of TV monitors, each one able to tap into any CCTV camera in the metropolitan area or broadcast live pictures directly from any Met helicopter.

Thorne and Holland took it all in. ‘And we were wondering why we couldn’t afford a new kettle at our place,’ Holland said.

A short, dark-haired woman rose from a desk in the red area and introduced herself as DI Louise Porter. Holland ran the kettle line past her during the minute or two of small talk. He looked pleased that she seemed to find it funny. Thorne was impressed with the effort she put in to pretending.

Porter quickly ran through the set-up of the team, one of three on the unit. It was a more or less standard structure. She was one of two DIs heading things up, with a dozen or so other officers, all working to a detective chief inspector. ‘DCI Hignett told me to apologise for not being here to meet you himself,’ Porter said, ‘but he’ll catch up with you later. And it’s three DIs now, of course.’ She nodded towards Thorne. ‘Thanks for mucking in.’

‘No problem,’ Thorne said.