But it wasn't over yet.

And anyone, even a cunning pro like Hook, could make a mistake.

Sir Henry Portman rose at seven a.m. on Thursday and, after showering and dressing, ate breakfast with his wife, Amelia, during which they discussed the dinner party they were hosting at the weekend, as well as the news being reported on Radio 4's Today programme that a terrorist plot to release poison gas in central London had been foiled the previous night. According to the surveillance operatives listening in, Sir Henry sounded perfectly normal, even feigning outrage at the callousness of the terrorists. 'What on earth is the world coming to?' they heard him saying.

After breakfast, he checked his business email account, answering a query regarding the terrorist attack from a private Jersey-based client, who wondered how it was going to effect HPP's positions. Sir Henry replied that it was too early to say, but a short-term fall in the market seemed likely, and thanks to HPP's recent bearish approach to blue-chip UK stocks, the fund would make some modest short-term gains.

At 8.30, Sir Henry's driver arrived at the five-storey Chelsea townhouse and he left for a prearranged 9.30 meeting with a London-based private client at the Landmark Hotel on the Marylebone Road, just west of Baker Street. He arrived twenty minutes early and took a seat in the open-plan dining area on the hotel's mezzanine floor, where he ordered a cappuccino and read the Financial Times until his client, a Mr Raif Mohammed, arrived at 9.25.

Their meeting, which was filmed covertly by surveillance officers sitting at a nearby table so that lip readers back at Scotland Yard could describe what was being said in real time, was polite yet tense. It seemed Mr Mohammed was less than impressed with HPP's current investments and it took all of Sir Henry's powers of persuasion to keep him from withdrawing his money from the fund.

While all this was going on, Bolt's team of twelve took up their positions. Two joined their colleagues in the Landmark dining area; a third took a seat in the foyer with a copy of the Sun; the remainder gathered near the hotel's main entrance. One of them, Kris Obanje, was on a motorbike; the others split themselves between four cars.

Bolt had had to give up the Jaguar he'd used on surveillance ops ever since his days in the NCS. It was undergoing a full steam clean to get rid of any traces of phosgene before being delivered to Thames Valley CID so that they could carry out an inspection and attempt to ascertain whether or not Bolt had been driving recklessly when he'd hit Rob Fallon. He didn't like his new car. It was an immense Mitsubishi Shogun 44, totally unsuited to London streets. Worse still, it was an automatic.

'They take all the pleasure out of driving,' he said, leaning against the car door, trying to get comfortable. 'I don't know what philistine invented them.'

Mo smiled. He was in a better mood now that he'd had a sleep and the danger from the gas had passed. 'You sound like Jeremy Clarkson, boss.'

'Jesus. Really? Well, he's got a point.'

'I don't like the way that prick Portman isn't feeling scared,' said a voice from the back seat.

Tina Boyd looked pale and she was sporting a black eye and a bandage across her nose, but even so, she'd made a pretty remarkable recovery. The hospital, having operated on her foot and put it in plaster, had wanted to keep her in for observation, but Tina was the kind of person who liked to make her own decisions, and she'd discharged herself at seven that morning and immediately phoned Bolt for an update.

As soon as she found out that his team was going to be following Sir Henry, she'd insisted on being involved. It had taken Bolt a lot of effort to persuade Big Barry to let Tina come along, and he'd swung it by explaining that she was better placed than anyone to ID Hook should he turn up, but he wasn't at all sure now that it was such a good idea. Tina had been quieter than he could remember in the hour the three of them had been in the car together, as if she was weighed down by an unseen burden. He couldn't help wondering what suffering she'd undergone at Hook's hands, indeed whether she would ever fully recover. He wanted to talk to her, offer words of comfort and support, but knew that now was not a good time.

'He probably doesn't even know we're on to him,' Bolt told her. 'There's no real reason why he should. It just means the look on his face is going to be even better when we finally nick him.'

'But even when we do it's going to be difficult to prove anything against him, isn't it?' she said quietly, staring out of the window.

'He'll fold,' said Bolt. 'Men like him always do.' He didn't elaborate. He hadn't told her about the Wise connection. He didn't think it was something she could handle hearing, not on top of everything else.

'Foot one to all units,' came a voice over the mike in the Shogun. 'Meeting's over and they're shaking hands. Sir Henry is now proceeding down the stairs alone. Over.'

'Foot two to all units,' said agent Cliff Yakonos, who was in the foyer with his copy of the Sun, 'I've got him. He's heading towards the front entrance. Just been met by his driver. Now they're both heading out. Over.'

Sir Henry's expected destination was HPP's office, which was in Grosvenor Square, but Bolt knew they could take no chances as he watched the two men come out of the hotel's front doors from their position twenty yards down the street on the main road.

Unlike his driver, who was small and non-descript, Sir Henry cut quite a dashing figure in his three-piece pinstripe suit and brightly coloured tie. He was a good-looking man, with a full head of curly grey hair and a strong patrician jawline, and he carried himself in the confident manner of a man used to being shown respect.

What a wanker, thought Bolt, not really registering the motorbike as it slowed down in front of the hotel entrance. It was only when the helmeted rider lifted his arm up straight and Sir Henry collapsed to the ground that he realized what was happening.

'Shit, he's down!' Bolt slammed the gearstick into drive and pulled out from the kerb, cutting up the traffic to a cacophony of horns, as the motorbike accelerated away. 'Car one to all units, target one has been shot. Suspect is escaping on a motorbike eastbound on the Marylebone Road.' He started reeling out the registration number into his mike, but the plate was badly mud-splattered (doubtless a deliberate act) and the bike was moving too fast as it weaved through the traffic, quickly putting thirty yards between them. 'We've still got visual,' he continued into the mike, 'but he's getting away. Now approaching the junction with Gloucester Place. Over.'

Mo slammed the flashing blue light on the dashboard as Bolt tailgated the car in front, beeping his horn and forcing it to pull over.

A second later, Obanje roared past him on the inside, riding a powerful Kawasaki 850, keeping a steady path along the white lines as he ate up the distance to the suspect bike. He was a highly experienced rider, unlike the man he was chasing, who didn't look entirely comfortable as he dodged between the cars.

'Bike one to car one,' shouted Obanje through the static and engine noise, 'I've got the eyeball. What do you want me to do? Over.'

'Car one to bike one, keep with him but don't get too close. He's armed and dangerous. Wait for assistance to intercept. Over.'

As he spoke, Bolt instinctively fingered the Smith and Wesson revolver he was carrying in a shoulder holster beneath his jacket. Because of the high-profile nature of both the target and the operation, most of the surveillance officers following Sir Henry were armed. Bolt, though, was the only member of his team who'd ever fired a shot in anger, something which didn't bode too well when you were trying to corner a highly trained professional killer. Luckily, though, their pursuit was being patched through to the operations room in Scotland Yard, so as long as Obanje kept the suspect bike in his sights, a trap could be set and CO19 could do the dirty work.