But Tina hadn't sounded unduly distressed. If anything, she'd sounded excited, which wasn't like her. The thing with Tina was that she tended to keep her emotions in check, and usually exhibited a businesslike calm that her colleagues occasionally found disconcerting. He'd offered her the rest of the day off, knowing that however brave a face she put on it she was still going to be shocked by what had happened, but knowing too that she'd refuse the offer, which of course she had. Tina Boyd wasn't the type who liked being treated with kid gloves, something that Bolt had always admired about her, and he'd told her to return to the Glasshouse and help out there.

Bolt was finding it increasingly hard to concentrate on anything but Emma's whereabouts and he knew he looked under stress. His fingers were glued to the steering wheel, and twice Mo had asked him whether everything was OK. He'd replied that he was fine, just tired, which wasn't an uncommon occurrence on his team. They regularly did sixty-, even seventy-hour weeks when they were on a job, but he'd felt bad not saying something to Mo about his plight. They were good friends who knew each other well. But Bolt was well aware that the moment he opened his mouth he'd put his colleague in an impossible situation. He'd done that once before, and had sworn then that he wouldn't risk their friendship a second time.

It had just turned twenty to six when they pulled up outside Andrea's house, having called through to the surveillance team to announce their arrival. Not surprisingly, the team leader reported that there'd been no suspicious activity in the street all day. The kidnappers, it seemed, were continuing to keep a low profile.

Bolt pressed the buzzer on the security gate, and they were let through without preamble. The garden looked even prettier in the dappled lateafternoon sunshine as he and Mo walked towards the front door. It opened and Andrea appeared, dressed in a white LA Fitness T-shirt and ill-fitting trackpants. She'd removed her make-up, and looked older. Her eyes were red, and there'd been recent tears.

'Any news?' she asked.

'I'm afraid not,' answered Bolt as she moved aside to let them in, 'but we've got a few questions we need to ask you.'

Matt Turner and Marie Cohen, the liaison officer, were in the hallway and Bolt nodded to them both as Andrea led them through to her living room. She took a seat on a long leather sofa while Bolt and Mo sat down in armchairs opposite her.

Marie leaned round the door and asked if anyone fancied a cup of tea. Bolt declined. Mo and Andrea both asked for coffee.

'What do you want to know?' she asked, lighting a cigarette with shaking hands and blowing out a line of pale blue smoke.

Bolt wasn't looking forward to this. It felt akin to kicking her when she was already down.

'We've heard from very reliable sources that Mr Phelan has a very large gambling debt. Did you know anything about that?'

She looked genuinely shocked. 'Are you sure? How big?'

'We believe it's tens of thousands of pounds.'

'Oh God, no. He's been staying out late quite a bit, but I had no idea he was gambling. What's he been betting on?'

'He's been losing it in a casino, but the point is, he owes a lot of money to some very nasty people.'

'Have you ever heard the name Leon Daroyce, Mrs Devern?' asked Mo, speaking for the first time.

She shook her head. 'Is he the person Pat owes the money to? Do you think he's the one who snatched Emma?'

'It's possible,' Bolt conceded. 'We don't know for certain. We think it might be that Mr Daroyce is currently looking for your husband to get the money he's owed.'

Andrea took another urgent drag on the cigarette. 'But surely he's the one with the motive. Are you not going to arrest him? Do something?'

'Mr Daroyce and his people are currently under surveillance, so if they are involved, we'll know about it very quickly.' Bolt paused. 'But our source tells us that your husband phoned Daroyce last Sunday night, saying he was going to get him his money in the next few days. That was only two days before the kidnapping.'

'So you're saying he is involved?' she asked, her voice cracking.

'We have to face up to the possibility that he is, yes.'

'He wouldn't do this, you know. He really cares for her.'

The room fell silent. Bolt leaned forward in his seat.

'What we keep coming back to, Andrea, is that if your husband wasn't a part of this conspiracy, how did the kidnappers know his and Emma's movements? We think the abduction happened in the car park of the dental surgery where Emma had her appointment.'

Andrea's eyes filled with tears. 'Don't use that word, abduction. It makes it seem, I don't know, like some paedophile snatched her and she's not coming back.'

'I'm sorry. Snatched. But the point is, the kidnappers knew she was going to be there. And we need to know how.'

Marie came back into the room with the coffee for Mo and Andrea. Andrea waved hers away.

'Who's got access to this house, Mrs Devern?' asked Mo, taking his coffee and thanking Marie. 'And who knows the code to your burglar alarm, aside from you, Mr Phelan and your daughter?'

'No one except the cleaner, and she's been doing the house for years.'

As Mo took down the cleaner's details, Bolt's mobile rang. It was the surveillance team leader. Bolt excused himself and walked to the other side of the room out of earshot.

'We've got an IC1 female stopping at Mrs Devern's security gate. Black hair, early forties. She'll be ringing the bell any moment now.'

The buzzer sounded in the hallway, and Matt Turner poked his head round the living-room door.

'Are we expecting anyone?' Bolt asked him.

'Not that I'm aware of.'

'OK, ignore it, then. Let's hope they go away.'

A few seconds later the buzzer sounded again, longer this time.

'Oh shit,' said the surveillance team leader down the phone.

'What is it?'

'She's unlocking the gate, and now she's coming through.'

Bolt cursed. This was the problem with operating out of a private address. He hung up as the key turned in the lock and the front door opened.

'Andrea?' came a woman's voice, followed immediately by an accusatory 'Who are you?' as she saw Turner.

'It's all right, Isobel, I'm in here,' Andrea called out, getting to her feet quickly. 'It's my business partner,' she added by way of explanation.

Bolt and Mo exchanged glances as Isobel Wheeler, the other half of Feminine Touch Health and Beauty Spas, came into view. She was a striking woman in her mid-forties whose shoulder-length black hair and olive skin suggested eastern Mediterranean parentage. She was wearing a short black dress that finished halfway down her thigh, and which Bolt thought would have suited a slightly younger woman, and black high-heeled court shoes. She didn't do a lot for Bolt, but he could see why some men might go for her.

Isobel and Andrea greeted each other with a kiss on both cheeks.

'I came to see whether you were feeling any better,' Isobel said, breaking away and surveying the room with a cool confidence that was only a hair's breadth short of arrogance. 'What's going on? Who are all these people?'

Bolt opened his mouth to reply but Andrea beat him to it. 'Pat's gone missing,' she said worriedly. 'I haven't seen him for days.'

Isobel looked shocked. 'Is that why you haven't been in this week? You weren't ill, then?'

Andrea shook her head. 'No. I've been waiting for him to come home, and he hasn't. The police are looking for him.'

'What do you think's happened? Did you have an argument or something?' There was something accusatory in Isobel's tone.

'No, it wasn't like that. He just didn't come home one night. I don't know what's happened.'

Isobel turned to Bolt. 'Why aren't you out there looking for him?'