'She's only just heard, apparently. Sounded quite upset.' Feeney gave Donovan the number, which she scribbled down on the back of one of the envelopes lying on the hall table.

'I'll try it now.'

Donovan hung up and dialled the number, but when she got through a man answered and said that Amanda was somewhere else in the exhibition hall. She left a message, with her mobile number, asking Amanda to call, then went back into the kitchen with the unopened post and phone, sat down at the table and started to leaf through the various envelopes. Amongst the usual bills and fliers, she spotted an envelope with just her name written on the front. It seemed to have been delivered by hand, as there was no stamp or address. She opened it and took out a postcard: Dear Sam, thanks for a lovely dinner on Saturday please thank Claire as well and for putting up with me and all my troubles. Things will get better! Just to let you know, I'll be holding you to your promise, whether you like it or not! Love Simon xx P.S. I remembered you grew up near Richmond and thought you might like this card.

The picture on the front looked vaguely familiar and she saw from the inscription on the back that it was a picture of the Thames, from Richmond Hill, painted by Turner; the view had barely changed in two centuries. She looked at the lovely, peaceful, sunny landscape, cows grazing in the foreground, the river snaking its way lazily into the hazy distance. Something nagged at the back of her mind. Simon certainly was thoughtful, although she had no recollection of telling him where she had grown up. Maybe Claire had said something. At least the tone was upbeat and more cheerful than the other evening. She had barely seen him since and she had been so busy that she had hardly given their conversation a moment's thought, but she wondered now if she had been rash to say she would have dinner with him. She had no desire to encourage him.

She was debating whether she ought to say something to him when she heard the sound of the doorbell. Reluctantly, she got up to answer it, expecting to find someone collecting for charity, or a child wanting sponsorship for something, those being the only callers at that time of night. Instead she found Simon Turner on the top step, brandishing a bottle of champagne in his hand like a trophy.

'Simon. What are you doing here?' she asked, trying not to sound too surprised or unfriendly.

He gave her his usual, easy-going, lop-sided smile. 'Hey, Sam. How you doing? Hope you don't mind my coming over, but I thought we should celebrate.'

'That's a nice idea,' she replied a little hesitantly.

'If you're busy, I can come back another time.'

'No. No, I'm not. Come on in.'

He seemed suddenly so huge, towering over her as he stepped into the small, low-ceilinged hall and bent down to give her a peck on the cheek. In spite of the temperature outside, he was coatless and, judging from the suit and tie, had come straight from work via an off-licence.

'Thought you only drank whisky,' she said, eying the expensive-looking bottle.

'And champagne, when there's something to celebrate.'

'Well, make yourself comfortable in there.' She gestured towards the sitting room. 'I'll go and get us a couple of glasses.'

She went into the kitchen and hunted around in the back of the cupboard until she found a couple of flutes. They hadn't been used for a long while and looked rather grimy. She wiped them hurriedly on a tea towel, hoping Turner wouldn't notice, and carried them back into the sitting room, just in time to hear the soft pop of the cork.

'Whoops,' Turner said, quickly grabbing a glass from her hand and holding it under the overflowing bottle. He shook the excess from his hand and licked his fingers, suddenly noticing the small wet patch on the carpet. 'Lucky it doesn't stain. Shall I get a cloth?'

'Don't worry about that. This floor's seen a lot worse.'

Little by little, he filled the glasses and then passed her one, which she took over to the armchair by the window. He sat down with his glass in the middle of the sofa opposite and sank back heavily against the cushions with a sigh, stretching his long legs out in front of him under the coffee table.

'What a day.' He smiled as he raised his glass. 'Cheers, Sam. Here's to you.'

'And to you. It must feel fantastic to have finally nailed Catherine Watson's murderer.'

He nodded and took a gulp of champagne. 'Never thought I'd see the day. I just hope Alan Gifford's watching from wherever he is, poor sod. He'd be real chuffed.' There was a pause, then he said, 'I suppose Mark's all full of himself now Carolyn Steele's golden boy and Superintendent Cornish's too, no doubt.'

Donovan gave him a weary look. 'Now don't go ruining the moment. You know he deserves most of the credit. He's the one who thought to look at Broadbent's photos, which gave us enough to arrest Jennings. He's also the one who worked out that Jennings was hiding something and he got Heather Williams to tell him about the gym and Jennings's friend, Daz.'

'Suppose so,' Turner said sullenly.

'Come on, Simon. You did your bit too. You found Jennings. Without him, there was nothing.'

He shook his head. 'Of course Mark would have found him in the blink of an eye, given half a chance.'

'Stop being bitter. It doesn't suit you. We're here to celebrate.' She raised her glass. 'Here's to you, Simon. And I mean that.'

He said nothing. Perhaps he felt he didn't deserve any praise.

'Anyway, the last thing Mark's doing is dancing around with glee. He's still fretting about the Holland Park murder. We still have no idea how Rachel Tenison and Jennings met, assuming he's the one responsible.'

Turner shrugged as if it didn't interest him and took another large mouthful of champagne.

'They must have come across one another in one of the bars she visited,' Donovan went on. 'But our only way of proving the link is to splash Jennings's photo all over the media and hope someone comes forward to say they saw them together.'

Turner was staring down at his glass as though mesmerised.

'Do you think Jennings is guilty?' Still no response. 'Simon?'

He looked up and frowned, as though she had interrupted his train of thought. 'Sorry, you lost me. What were you saying?'

'I asked if you honestly think that Jennings is responsible for the Holland Park murder.'

'He's the obvious candidate, isn't he?' he said without enthusiasm. 'But I don't see him owning up to it in a million years. I'm afraid Mark may have to learn to live without a conviction.'

Deciding it was time to steer him off anything to do with Tartaglia, she was about to ask him if he felt like something to eat when she heard the distant ringing of her mobile coming from the kitchen.

'Back in a sec,' she said, putting down her glass and racing along the corridor. She grabbed the phone from the table and flipped it open.

'Hello?'

'This is Amanda Wade. Is that Detective Sergeant Donovan?'

'Yes. Thanks for calling back.'

Getting a paper and pen from her bag in the hall, Donovan sat down at the kitchen table and explained the background to why they wanted to talk to her.

'How long did you work at the gallery?'

'Just four months, up until last Christmas. Then I went off on my travels.'

She had a girlish, breathy Home Counties voice, as though she had just walked straight off the hockey pitch. Donovan pictured a clone of the current gallery assistant, Selina, all silky blonde hair, short skirt and endless toned legs.

'Why such a short time?'

'I was temping. I was only supposed to be there for a month or so while they looked for someone permanent, but I ended up staying longer than expected. I liked working there and they were having problems finding the right person.' She sighed heavily. Donovan was about to ask another question when she added, 'I liked Rachel. She was nice to work for. I'm very, very sorry she's dead.'

'I know this must be upsetting for you, Miss Wade. Would you rather I call back another time?'

'Really, I'm OK. I'll be fine. Please carry on.'

'We're trying to find out about Miss Tenison's friends, particularly male friends, and anyone who she may have been involved with romantically. Unfortunately, at the moment we're drawing a bit of a blank. Can you remember anyone she might have seen or talked to?'

There was a pause at the other end before Amanda spoke. 'Men used to call her, of course. But apart from her brother, there wasn't anybody in particular.'

'There must have been someone else.'

'Well, there was a journalist, Jonathan something.'

'Bourne?'

'Maybe. He used to ring from time to time. She said he was a friend...'

with Donovan heard the doubt in her tone. 'We know about him,' she replied.

Bourne was still a suspect without an alibi, but if he had killed Rachel Tenison there were no means of knowing how he had found out the details of the Watson case. 'Is there anybody else you can think of? Even someone she didn't seem to know that well? Anyone hanging around?'

There was another pause. 'Well, there was someone. Again she said he was just a friend. She made quite a point of it, in fact, although anyone could see that he couldn't take his eyes off her. He came into the gallery a couple of times when I was there.'

'Do you mean a client?'

'Goodness no. You can tell. And she didn't seem that pleased to see him. Each time she whisked him off somewhere quite quickly, like she wasn't comfortable him there, although he seemed perfectly nice to me.'

Wondering if the man was Jennings, Donovan asked, 'Was he bothering her?'

'Not then, not actually bothering her. But there was another time. There's a cafe right opposite the gallery-'

'I know it,' Donovan said. It was where she and Minderedes had bought coffee.

'Well, I saw him sitting outside at one of the tables on the pavement one day. He was just staring into the gallery, bold as brass. I could see him from my desk and it was very odd indeed. Really quite unnerving.'

'Did she know he was there?'

'I watched him for a while and when he didn't leave, I went downstairs to her office and told her. She came up and took a look. When she saw who it was she just said, "Don't worry about him; he'll go away." The way she said it, I got the feeling it had happened before.'

'And did he go away?'

'No. Half an hour later he was still sitting there, still watching. It was freezing but he didn't seem to mind. He had a cup of coffee or something in front of him but I never saw him drink it. It must have been stone cold but he wouldn't let them take it away. I went downstairs again and told her. I thought it was quite creepy.'

'Why didn't you speak to Richard Greville? Or call the police?'

'Richard wasn't there, I'm sure. I suggested calling the police but Rachel wouldn't let me. Said she'd deal with it. She put on her coat and went out to speak to him.'

'Did you see what happened?'

There was another hesitation followed by a sigh. 'Well, I couldn't help being curious, could I? And I was worried for her, so I kept an eye on him. But nothing happened. She just went across the street and said something to him. Then she came back into the gallery and went downstairs.'

'What did the man do?'

'He sat there for a moment then he got up and left.'

'He didn't come back?'

'Not that I know of.'

'When was this?'

'Just before I left. Early December, I think.'

'Can you describe him?'

'Yes. Yes, I can. He was very tall. I'm about five nine in my heels but he towered over me. He had very short, very blond hair and the most extraordinary eyes. They were the most striking thing about him.'

'In what way?'

'They were pale blue, like one of those dogs. You know, huskies.'

'Was there anything else?'

'Well, I think she said he was a policeman, although maybe I've got that bit wrong.'

As Amanda spoke, Donovan's eyes fell on the postcard from Simon Turner. She knew what had been bothering her before. It was his handwriting: the same, distinctive, backwards sloping writing she had seen before on the card sent to Rachel Tenison. Only the colour of the ink was different. That's what had muddled her. She remembered the words and the obsessive, plaintive tone. It was as if someone had moved the tuner on the radio and in place of the hiss of static, everything was sharp and clear.

Her breath caught in her throat. 'A policeman?' She barely heard herself say it.

'Yes. Or a detective,' Amanda babbled away in the background. 'When I said I was going to call the police, Rachel laughed and said there wasn't any point. She said it would be like taking coals to Newcastle. Maybe she meant he was a private detective and he was keeping watch on her.'

'Do you remember his name?' Simon. Simon Turner. As she waited for Amanda to say it, she thought of him sitting only a few feet away in the other room, knocking back his champagne. What the hell was she going to do? Her hand was trembling as she held the phone to her ear and she leaned back against the wall for support. She must try and keep calm until she could end the call.

'No. I'm sure she never mentioned it.'

'But you'd be able to identify him if you saw him?'

'I think so, although put him in a room with a load of Scandinavians and I'm not so sure.'

'Do you have any idea how they met?'

'No. Hang on a sec.' Donovan heard a man's voice in the background at the other end, then Amanda came back on the line. 'I'm sorry, but some clients have just arrived and I've got to go. Is there anything else you wanted to know?'

'I think we've covered everything for now. We'll need you to put this in writing. I'll get one of my colleagues to call you tomorrow.'

Trying to focus on the task in hand, she thanked Amanda for her time and ended the call.

As she snapped her phone shut, she heard Turner's voice right behind her.

'Came to give you a top up.'

She wheeled around and stared at him.

He was carrying the bottle and his glass, which he had refilled. 'Sorry. Didn't mean to give you a fright,' he said, putting the bottle down on the table. He peered at her.

'You OK, Sam? You look like you've seen a ghost.'