‘Nice little boutique place on Threadneedle Street, just round the corner from the Gherkin.’

‘Any good?’

‘A bit quiet,’ Ken shrugged. ‘First-class breakfast, mind you.’

Across the street, a black cab with its light on had slowed. As a gap in the traffic opened, it executed a tight U-turn and pulled in at the kerb beside them. Naysmith reached out and held the door open.

‘Come on,’ he said, ‘I can drop you on my way – I’m out by Canary Wharf.’

They told the cabbie where they were going, then settled back into the broad rear seat and gazed out at the bright shopfronts as the taxi set off. Crackling snatches of conversation and static drifted through the hatch from the driver’s radio.

‘So are you happy at Winterhill?’ It was an abrupt question, but Ken had always been the master of the surprise attack.

‘Yes.’ Naysmith shot him a quizzical look. ‘Why do you ask?’

‘Don’t get me wrong, but it doesn’t sound like it’s stretching you,’ the Welshman explained. ‘You were always one for a challenge, that’s all.’

‘There’re plenty of challenges . . . if you know where to look.’

Ken nodded, studying him.

‘So you’re enjoying it there?’

Naysmith thought for a moment.

‘It gives me freedom, and that suits me just now.’ He relaxed into his seat, tilting his head back, then grinned over at his former colleague. ‘Why, are you going to make me an offer I can’t refuse?’

‘Well, what could be better than working with me?’ Ken winked at him. ‘Just like old times, eh? Dream ticket and all that . . .’

Naysmith laughed.

‘I’m flattered,’ he said, ‘but I’m not sure this is the right time for me to move. Ask me again in a few months.’

‘The offer might not be there.’ Ken shook his head in mock seriousness. ‘Hell hath no fury, and so forth . . .’

They drove on into the financial district, where the cars were less frequent but more expensive. A white Ferrari pulled up beside them at a junction, then sped away with a roar when the lights turned green.

‘Tell me that wasn’t what tonight was all about . . .’ Naysmith left the question hanging.

‘Not at all, not at all.’ Ken smiled, then leaned over conspiratorially, making the vinyl seat cover creak. ‘I was really hoping to get some decent client leads off you, but you’ve been a cagey so-and-so even after three bottles of vino collapso.’

They laughed as the taxi pulled up outside the small hotel.

‘You never change, Ken.’

‘Neither do you.’ Hunching over, he struggled out onto the pavement, then straightened up and adjusted his spectacles with a grin. ‘You need a challenge, you do.’

Naysmith smiled back.

‘I’ll try and keep busy,’ he said, softly.

The city slid by, bathed in the lonely orange glow of street lights and illuminated signs. Knots of people drifted like eddies in the current, silhouettes against the glaring shop windows as the taxi paused then sped on again.

Naysmith held up his watch so that it was lit by the headlights of the car behind them: 11.07 p.m. Just over nine hours until he could begin what promised to be an interesting game. The conference meant he’d be in London until the end of the week and he wondered how far he might progress things in that time . . . Crucially, would he be able to find his target again by Friday?

The taxi rattled along a sweeping curve, then finally slowed as it turned in to stop just outside his hotel, the engine idling.

‘Here you are,’ the cabbie called over his shoulder, stopping the meter. Naysmith sat forward in his seat and was just reaching for his wallet when he felt the vibration of his phone in his jacket pocket. Frowning, he took it out, saw Kim’s name on the screen and busied the call. He always felt it rude to answer the phone when you were dealing with someone else.

Once he’d fished out his wallet, he paid the fare, folded the receipt into his pocket and clambered out. The taxi drove noisily away, leaving Naysmith at the foot of the carpeted steps, bathed in light that spilled from the glass doors.

Yawning, he made his way into the foyer, his phone pressed to his ear. Kim sounded odd when she answered.

‘Hello?’

‘Hi. Sorry about that, I was just getting out of a cab.’

There was a pause.

‘Where are you now?’ she asked, quietly.

‘Back at the hotel. Just heading up to the room now,’ he replied.

What was the matter with her? Was she tired? It wasn’t really that late.

‘Okay.’

Another pause.

‘Are you alone?’ she asked.

Naysmith stopped at the foot of the stairs and leaned back wearily against the wall. Demons of suspicion took his place when he left her by herself.

‘Of course I’m alone,’ he sighed. ‘And what’s that supposed to mean anyway?’

‘Nothing.’

‘Don’t start this, Kim,’ he warned her. ‘I’ve been at the conference all bloody day and catching up with Ken from TTC this evening. Just him and me, in a restaurant, talking about work. Okay?’

‘Okay.’

She sounded as though she was beginning to believe him. And this time, it was actually the truth, for heaven’s sake.

‘And I busied the phone because I was paying the taxi driver. Really, you’re being paranoid.’

She began babbling out an awkward apology. Once they started apologising, you knew that going on the offensive had worked, that you had them where you wanted them.

‘It’s okay,’ he hushed her. This was really the time to press his advantage, to make her feel so foolish that she wouldn’t dare question him again. And yet he found that he didn’t want to do that. Not to her. He imagined her huddled in the corner of the living-room sofa, her feet tucked under her as she cradled the phone, strands of hair falling across her anxious face. No, not to her.

Changing the subject now would let her off the hook completely.

‘Anyway,’ he said, ‘while we were out Ken offered me a job.’

‘Really?’

‘Really. We worked well together before, so it makes sense for him.’

‘What did you say to him?’

‘I told him I’d think about it,’ he lied, patiently.

‘Oh Rob,’ she said softly. ‘I’m sorry about everything. Sometimes I just get worried about things, you know?’

‘All you have to do is trust me,’ he told her. ‘Everything else will work itself out.’

There was a steady drizzle the next morning. Naysmith sat on a cold metal bench and gazed along the station platform, his mood as bleak as the grey sky overhead. It had seemed quite simple in theory, but the reality was different – it was almost impossible to spot someone if you didn’t know which train they were going to be on.

He’d only been at Poplar for twenty minutes or so, but already it was enough to convince him that he wouldn’t find the sandy-haired man today. Naturally, he’d not started looking until 8.27 a.m. – the twenty-four-hour grace period was sacrosanct – and if the target had travelled by an earlier train they would have missed each other.

Nevertheless, it seemed unlikely that he’d locate him this way. The DLR trains were short and reasonably well lit, but it was still difficult to see exactly who was inside each carriage. He’d tried standing towards the end of the platform, so that the length of the train had to move past him as it entered the station, but it was no good. The windows whipped by too quickly, people were moving around inside and, worst of all, he could only really see the passengers sitting on his side of the train. It simply wouldn’t work.

He sat back and rubbed the sleep from his eyes – too much wine with Ken last night. Stifling a yawn, he stretched and gazed out at the overcast city. If he was going to find the target, his best chance would be to spot him while he was on a platform, either before he got on his train, or after he got off.

He stood up and wandered over to study a large route map on the wall behind the seats. His finger traced along the blue-green DLR line until he found Poplar, where they’d first made eye contact. The train had been heading into the city, so the target would have got on somewhere before that. But where? There were two different routes leading in from East London, and an awful lot of stations to cover . . .