Bolt stood in the hospital car park, breathing in the cool night air. The rain had stopped completely now, leaving behind the smell of late summer foliage. He'd just finished paying the man from Autoglass, who'd put a new windscreen on the Jag, and he was pissed off.

To have come so close to Hook – the man he'd been after for five years – and then lose him wasn't easy to stomach, particularly with Tina unaccounted for. But it could have been worse. They'd almost lost Fallon as well. When they'd arrived at the hospital earlier and run into the ARV team tasked with guarding Fallon at the entrance, they'd heard the commotion and had run through accident and emergency, disturbing Hook, who'd abandoned his pursuit of Fallon and fled, using two orderlies and their gurney as cover. Bolt had even caught a glimpse of him, thirty yards away down the end of a corridor. So near, yet so bloody far.

His mobile started ringing.

It was Big Barry Freud. 'What on earth's going on, Mike?' he demanded. 'I've just had a call from the assistant chief constable of Thames Valley Police. He says you've been involved in a shoot-out in Berkshire, ran someone over, and drove off in a car that was being treated as crime-scene evidence. Care to explain?'

When he put it like that, it didn't sound too good, but Bolt was fairly certain that his actions had helped save Fallon's life, which was going to earn him some sort of credit. He gave Barry a brief rundown of the situation.

'So you're saying it's all to do with this bloody kidnap that Tina Boyd's been investigating?'

'It looks that way. Hook's definitely trying to do everything he can to shut up Fallon. And he's taking some massive risks. Like coming here tonight.'

'Blimey. It must be a very lucrative kidnapping to be worth all this effort and this many murders. What do we know about this girl?'

'Her name's Jenny Brakspear. And it's not a lot, but according to Tina, her father denied that any kidnapping had actually taken place. He said she'd gone on holiday. I had one of the team check up on Jenny's and her dad's backgrounds earlier, but everything ended up being put to one side when we got the call about Tina, and I haven't got the results back yet.'

'I heard that the body wasn't Tina's.'

'No.' Bolt knew he should have phoned Barry and told him it wasn't, but things had been happening so fast that night there'd been hardly a moment to stop and think.

'And you still haven't heard from her?'

Bolt sighed. 'No we haven't. But we've talked to Fallon.'

'Was he any help?'

'He's filled us in on what happened, but the problem is he didn't really know Jenny that well.'

'Great.' Big Barry exhaled loudly down the phone. 'Which of the team was looking into Jenny's background?'

'Kris Obanje. I think Mo's on the phone to him now.' Bolt looked across to where his colleague was standing on the hospital steps, talking animatedly into his mobile and taking notes at the same time.

'Good. Find out what you can and keep me in the loop. I'm at home.'

Bolt said he would, and ended the call. It was 1.20 in the morning, and he was exhausted. But he had a feeling neither he nor Mo Khan were going to be sleeping any time soon.

'According to Obanje, Jenny Brakspear's a complete unknown,' said Mo, pocketing his phone. 'Currently unemployed. She worked for an internet travel company based in Islington until about three months ago but got made redundant because of the credit crunch. No criminal record. Just an ordinary middle-class girl.'

'Her dad's the key,' said Bolt. 'He's the one they've got to be blackmailing. What did Obanje find out about him?'

'He's a company director of a gas wholesaler based in Cambridge. Good salary, and he's a part owner of the company, but there's not enough to hold him to ransom over. If he liquidated all his assets tomorrow then Kris reckons he could probably raise a few hundred thousand, but he hasn't even attempted to do that. The company's listed on AIM, the small company stock exchange, and there've been no share transactions this week, which there would have been if he'd been trying to raise money by selling his shares.'

'So it's something else.'

They both stood in silence for a minute.

Then a thought struck Bolt. 'You said Brakspear's a director of a gas company. What type of gases do they deal with?'

Mo shrugged. 'I don't know, and I don't think Kris looked into it in too much detail. But they wouldn't be ransoming her for gas, would they? It can't be worth that much money.'

'But if it's not money, I don't know what else it could be. Have you got a name for the company?'

He flicked open his notebook. 'Mainline Gas Services.'

'Let's look them up.'

Mo Khan always kept his laptop with him on jobs. It was currently under the seat in the Jaguar. They got inside the car and he looked up Mainline on the net, using a plug-in stick.

The company's website was pretty basic. It gave a brief history and an even briefer description of the services offered, and the gases they dealt with, none of which looked particularly controversial, although Bolt knew that this didn't mean much.

Mainline had two directors. One was Roy Brakspear, and when Mo double-clicked on his name the photograph of an ordinary-looking man in his fifties with grey hair and an avuncular smile appeared. His background was equally ordinary. A Masters degree in Chemistry from Cambridge; twelve years as a chemist at ICI before founding Mainline with an ICI colleague in 1987; one adult daughter. No mention of a wife. The ICI colleague was Miles Cavendish, now managing director, a younger-looking guy with red hair in a side parting and a much more confident, go-getting smile in his website photo.

'We need to speak to this guy,' said Bolt, pointing at Cavendish's mug.

'He's not going to be pleased being woken at this time in the morning.'

'It's an emergency. We've got no choice.'

It only took a few minutes to find Cavendish's number. SOCA had access to every registered telephone number in the country, but in this case Bolt bypassed HQ and phoned directory enquiries, immediately striking gold.

'This guy must be one of the last people in the country listed in the phone book,' he said as he wrote down the number. 'I'd never have my number there for every Tom, Dick and Harry to see.'

Mo shrugged. 'Saira insists on it. Just in case any of her old friends are trying to look her up.'

'And do any?'

'No. All we get are calls from Indian call centres.'

'I think when he finds out what this is about, Cavendish is going to wish we were an Indian call centre.'

He dialled the number. The phone seemed to ring for ever. Bolt was just about to give up when a hugely irritated male voice came over the line. 'Yes?'

'Miles Cavendish?'

'That's me,' he answered, still not sounding quite awake. 'Who am I speaking to, please?'

Bolt introduced himself and heard the audible intake of breath. No one likes a call from SOCA.

'How can I help you?' There was concern in his voice.

Bolt knew he had to choose his words carefully. He needed answers but he didn't want to have to give too much away. 'Can you tell me if your company, Mainline, handles any gases that could be described as expensive? Or dangerous?'

'Excuse me, can you explain what on earth this is all about? It's half past one in the morning.'

'Can you please answer the question, sir?'

'Look,' snapped Cavendish, 'how do I even know you are who you say you are? You could be anyone. Let me call you back.'

'I'm on a mobile.'

'In that case, goodbye. I'm not talking to people whose credentials I can't see.'

Bolt started to say something else but he was talking into a dead phone, and when he called back it was engaged. He shook his head angrily. 'Arsehole,' he cursed.