'You said there was another suspect.'

'Yeah. Michael Jennings. He was one of Watson's students, flunked his year-end exams for some reason and she was helping him with some extra tuition.'

'He went to her flat?'

'No. They only ever met at the college. But a witness saw a man matching Jennings's description walking along Watson's street at roughly eight o'clock that evening. Said he saw him go into Watson's house, although there were several people going into the house that night as the bunch of Kiwis on the top floor were having a party. Problem was, the witness was a local junkie and not a hundred per cent reliable. He failed to pick Jennings out of a line-up and we had bugger all else to place him at the scene. In the end, we were forced to let it drop.'

'Were those the only two suspects?'

Turner nodded. 'We interviewed her family, friends and former lovers, as well as all her work colleagues and students. We took over six hundred calls following the Crimewatch appeal and checked out every single one, however dodgy. We trawled through the sex offenders' register, followed up on anyone, of any age and background, with a conviction for rape or attempted rape living either in that part of London or close to where Catherine Watson worked. But no new leads came to light. It was Alan Gifford's last case before he popped his clogs. I think it finished him off.'

'What do you mean?'

Turner gave her a weary look. 'You know what they say, don't you? Never let a case get under your skin, never get emotionally involved. Well, Alan forgot all of that. It was like he was on a crusade, the only bloody knight in shining armour Catherine Watson ever had. He was tired most of the time, on some sort of medication, I discovered later. He'd just been through a really messy divorce and he was ill, though he didn't know it then. That sort of stuff can mess with your mind and screw up your judgement, big time. He probably knew it would be his last big case before he took retirement, probably wanted to go out with a bang. Anyway, he let himself get right in deep, became obsessed with finding Catherine Watson's killer, almost had a personal vendetta going against Broadbent, as if he was the only man left to defend her honour. And he failed her, like all the rest.'

Donovan had been sipping her wine as he talked and she finished the final mouthful, thinking through everything he had told her, wondering what Tartaglia would make of it. 'Did you think it was Broadbent?' she asked, after a moment. 'Did you agree with Alan Gifford?'

Turner shrugged. 'I wasn't as sure, if I'm honest. But then I didn't have Alan's experience. I agreed with him that the killer was likely to be someone known to Catherine Watson. There were no similar attacks either in the area or anywhere else in London at the time. Even though the press started getting their knickers in a twist about a serial killer on the loose, it was a load of rubbish. To me it was simple. Catherine Watson was a cautious, careful woman. She had good security on her door, proper locks and bolts, almost overkill, like she was worried about such things. She wouldn't have let someone into her flat unless she trusted them. There was a theory that there might have been more than one person with her. The bloke who lived below in the basement thought he heard several people walking around. But the floorboards are creaky and there was the music playing loud. We never got very far with it as an idea.'

'You said she was lonely. Do you think she picked up men for sex?' Donovan asked, wondering about a possible link with Rachel Tenison.

'If she did, we found no trace of it. From what I know of Catherine, she wasn't the type to go cruising bars, if that's what you mean. I got the impression she was a romantic, looking for Mr Right. She was just bad at picking them.'

'What about her boyfriends?'

'We did a thorough background search on all of them, going back several years. But we couldn't put any of them in the frame. In the end, we kept coming back to the same thing: if it wasn't Broadbent or, possibly, as a long shot, Jennings...who the hell else could it be?'

14.

Tartaglia went into the sitting room and closed the shutters. The boxes containing the Catherine Watson case files were sitting by the front door where Wightman had dropped them off earlier. He bent down and dug around inside until he found what he wanted, then crossed the room to the sofa and sat down. Starting with the photographs of the crime scene, he leafed through until he came to the images of the dead Catherine Watson. She was lying on her back, face up, in some shots covered by a blanket, in others, the blanket had been removed and she lay exposed and naked. Close-ups showed the extent of her injuries: bruising and cuts around her mouth, where it looked as though she had been hit; deep ligature marks at her wrists, ankles and neck where she had been tightly bound at some point while still alive, although there was no sign of the materials used to do this. He was used to seeing such images, but they never failed to affect him, particularly when a child or a woman was the victim. As he gazed at her white, vacant face, noticing the smudges and tear trails of mascara around her eyes, he said a silent prayer for her.

He lit a cigarette, wondering what, if anything, she had had in common with Rachel Tenison. The nature of some of her injuries was the only thing so far to suggest any connection, and there wasn't a clear and direct parallel. He turned his attention to the post mortem report. It suggested that handcuffs and possibly rope or cord had been used to secure her while alive. Shallow cut-marks were found on her breasts and abdomen, consistent with a sharp blade, and she had been raped, sodomised, and strangled with some form of ligature. Traces of cotton wool had been found in her mouth, presumably used as part of the gag. Taking out the exhibits file, he found a note saying that several short lengths of cord, a wad of cotton wool and a pair of flesh-coloured women's tights had been recovered from the scene. There was a further note to say that an open packet containing an identical type of cotton wool had been found in the cupboard in Watson's bathroom.

He put them down and opened the manila folder containing the closing report, which summarised the case. Catherine Watson had last been seen at five-thirty on the Saturday evening when she had gone into a local shop to buy various items of food. A till receipt recovered from the kitchen bin listed milk, bread, cream, bacon, parmesan, eggs, spaghetti, strawberries, a bag of salad and a tub of Green & Black's vanilla ice cream, along with a bottle of Australian cabernet sauvignon and candles. Looking at the items, it occurred to him that she had been planning on preparing a spaghetti carbonara, and the wine and candles suggested she was making a special effort for someone. Had she been excited, looking forward to that evening? Had she trusted the wrong person and invited in her killer? It was a poignant thought.

Catherine Watson's body had been discovered by a neighbour, Malcolm Broadbent, at around nine o'clock on Sunday morning and the emergency services had arrived at nine-sixteen, a doctor pronouncing her dead at nine-twenty-two. According to the report from the pathologist who had attended the scene, she had been dead for at least six hours, which put the estimated time of death in the early hours of the morning.

Reading further, it had been assumed that she had never gone to bed that night: the bed was still made and her nightdress neatly folded under her pillow. Most importantly, there were no signs of a break-in. The back door, which led to the garden, with access down a small passageway to the main road, was firmly locked and bolted and it seemed likely that she had let the killer in through the front door. There were no reports of shouting or screams or anything unusual, apart from the fact that the occupant of the basement flat said Catherine Watson had been playing music unusually loud and late that night. But as it was Saturday night, and the tenants on the top floor were holding a party and making a lot of noise too, nobody had bothered to ask her to turn it down. Her neighbour in the flat below thought he heard music and footsteps until well after one o'clock in the morning, but there had been a lot of coming and going on the staircase related to the party on the top floor and he wasn't a hundred per cent positive that it had all come from her flat. According to the report, based on the nature of her injuries and the witness statements, the killer had taken his time and tortured her over a period of several hours.

Tartaglia turned the series of events over in his mind, thinking back to what was known about Rachel Tenison's final movements. If Jonathan Bourne had been telling the truth, which was a big if, she too had had a mystery caller. The assault on Catherine Watson had been considerably more violent, but in her case what had happened was unlikely to have been consensual. Perhaps the greater the resistance, the greater the violence used, as was often the case with rape.

Inside one of the folders he found the crime scene footage taken by one of the forensic team, neatly labelled with date, time and Catherine Watson's address. He switched on the TV and slid the DVD into the player. The initial images showed a wide, busy suburban street, with rows of tall houses on either side. A bus and several cars sped past, along with several passers-by, one stopping and grinning inanely at the camera over the crime scene tape before being waved on by a uniformed officer. A moment later, the camera zoomed in on the shabby exterior of the house where Catherine Watson had lived. Moving forwards, it focused first on the tall hedge and wooden gate that marked the boundary with the pavement, then lingered on the paved front garden behind, with its collection of rubbish bins. Then up a flight of steps and in through the open front door, panning the dark communal hall before switching to the door on the left, the entrance to the ground floor flat.

The door opened immediately into a large sitting room with white walls. Weak winter sunlight flooded in through a large bay window, bleaching the frayed brown carpet; motes of dust danced in the shafts of light. The camera took in the limp, floral-patterned curtains and tired furnishings, the cheap paper shade on the ceiling light, the full-to-bursting rows of books on either side of the marble fireplace. Framed photographs of a couple of young children sat on the mantelshelf, along with a plant in a ceramic container and a pair of white china candlesticks. The candles were burned down to stumps, solid rivulets of crimson wax flowing over the sides and onto the shelf of the chimneypiece. Were they the ones Catherine Watson had bought earlier in the day?

A couple of large floor cushions formed a seat in the bay window, a pen, some sheets of paper and a couple of books on the floor beside them, where Watson must have been sitting working or reading in the sunshine. According to the report, her body had been found in the sitting room, but as the camera panned the interior, Tartaglia saw no signs of a struggle.

The footage that followed revealed a dark hallway, followed by a small shower room and an L-shaped kitchen in what appeared to be an extension at the back. Judging by the array of cookbooks and tidy rows of kilner jars on the shelves, Catherine Watson had liked to cook. Again, everything seemed to be in its place. The camera lingered briefly on windows and a back door, showing that they were closed, their locks un-tampered with, then travelled a little shakily back down the hall into the bedroom.

The curtains were open and no extra light was needed to see Watson's naked body. She lay in the middle of the double bed, arms at her sides, as if asleep. As the camera zoomed in on the deep, dark marks at her ankles, wrists and neck, Tartaglia wondered again about the significance of the open curtains and the candles.

He decided he had seen enough for the moment and stopped the disc. He pulled out some more photographs and found a three-quarter length shot of Watson taken when alive. It was a sunny summer's day and she was leaning against the stone pillar of some sort of classical style building, arms folded in a relaxed fashion, smiling. He couldn't tell if she was tall or short, but she had a decent figure and nice legs, even if the baggy skirt and blouse she was wearing did her no favours. She had shoulder-length, wavy brown hair and a broad, pleasantly fleshy face, with a wide mouth. She wore little or no make-up from what he could tell. Her expression seemed to radiate an easy warmth and kindness and he pictured her as the sort of woman people would go to with their problems, although maybe he was reading too much into the image. From a purely physical point of view, he couldn't see any resemblance between Catherine and Rachel.

With more questions than answers, he suddenly realised he was hungry and looked at his watch. The rest of the files would have to wait until later.

He picked up his phone and dialled Donovan's mobile. She answered almost immediately.

'I'm at home,' he said. 'Have you found Turner?'

'He's with me now. We've been having a drink. He's been telling me about the Watson case. We were just about to go and get a Chinese.'

'Well, make it a take-out and order something for me too,' he said impatiently. 'And some beers while you're at it. I want you both over here now. I need to talk to him.'

'Broadbent opened the curtains in both rooms, from what we could tell,' Turner said, lazily.

He gave a wide yawn, scattering cigarette ash with one hand as he spoke, a fresh tumbler of whisky clasped at a dangerous angle in the other. Surrounded by the debris of plates and discarded food cartons, he lay at Donovan's feet in a cloud of smoke, spread-eagled like a pasha on the floor, head and shoulders propped up on a pile of cushions.

Tartaglia had opened the window a few inches to clear the air and Donovan could feel the cold, damp draught on her shoulders. The soft pattering of rain was lulling her to sleep and she stretched in the depths of her chair, flexing her legs and fighting off the urge to put her feet up on Tartaglia's expensive-looking glass coffee table. She felt incredibly tired, happy just to listen and let the two of them do the talking. She sensed Tartaglia's growing impatience, but there was no hurrying Turner. He had polished off several inches of Tartaglia's Glenfiddich and was threatening to finish the rest, the many whiskies of the evening finally beginning to take their toll even on a man of his size. He usually held his drink better than most but Donovan had never seen him tank back so much before, certainly never seen him half-cut the way he was now. Nor had she ever seen him chain-smoke his way through so many cigarettes. God only knew what he would smell like in the morning.

'What about the body?' Tartaglia asked.

'Broadbent moved it. Said she was in the sitting room when he found her. Took her into the bedroom. Un-gagged her. Cut off the tape that was binding her. Laid her out on the bed with a blanket over her.'

'Why did he do that?' Tartaglia asked.

Turner shrugged. 'Said he thought she was still alive.'

'Going back to the Saturday night, she went shopping for food in the afternoon. It says on the till receipt that she bought a bottle of wine and candles...'

'Yeah. Looked like she had a date.'

'According to the post mortem report, her stomach was empty apart from the wine.'

Turner nodded. 'Check the files. You'll see a note of what was found in the bin. A whole load of cooked food, some sort of pasta from memory certainly enough for two, nothing eaten. The empty wine bottle was there. Somebody cleared everything away. Washed the dishes.'

'That's the sort of guest I like,' Tartaglia said, looking at Turner. But it was water off a duck's back. 'So, she had a date. You never found out who it was with.'

'Her diary was blank for that evening,' Turner said wearily. 'Blank for most evenings, poor, sad cow.'

'You checked her email?'

'Course. And her phone. But nothing gave.'

'So it must have been a verbal arrangement. Maybe she bumped into someone and asked them over.'

Turner nodded again. 'Maybe. Course, we checked her movements in the days before she died but never turned up anything.'

'What was she wearing?' Donovan asked.

'Never found the clothes.'

'She was wearing make-up, according to the report,' Tartaglia said. 'Sounds like she had made an effort for someone.'

Turner shrugged again and took another sip of whisky.

A moment's silence followed, before Tartaglia spoke again. 'There's no point wasting any more time on this. The Watson case is cold. You and Gifford did all you could by the sounds of it, and the review team failed to turn up anything new. The only point is how this relates to Rachel Tenison.'

'Can't help you there,' Turner said, eyes half closed.

There was another long pause. Tartaglia stretched his legs out in front of him, arms behind his head, and stared vacantly into the centre of the room. Donovan wondered what he was thinking. He looked tired, still in his work clothes, a dense shadow of stubble on his face, his wavy black hair a little dishevelled. He was clearly disappointed that there wasn't an immediately clear link between the two cases, but life was never that easy.

After a moment Tartaglia slapped his thighs and got to his feet. 'Think we're done for the night. Don't you?'

He caught Donovan's eye as he bent down and started to clear up the debris on the floor. She rose to help him, leaving Turner still glued to his cushions.

Tartaglia collected up the plates and was about to go to the kitchen when he looked over at Turner. 'Do you have any idea what position Catherine Watson was in when she was originally found?'

'You mean by Broadbent?'

'Yes.'

'We did a reconstruction. Should be some photos in there.' He waved vaguely at the box of files sitting by the door, sending another tube of ash onto the floor. 'We had him go over it many times, tried to catch him out, but he stuck to the story...'bout the only thing he did stick to. Never changed the details one jot.' He stared down at his glass, seemed surprised that it was empty, and reached for the bottle beside him.

'OK. I'll look at it later. But did the injuries to her body match what he described?'

'Yeah.' Turner exhaled loudly and frowned. 'Maybe he was telling the truth about that bit.'

Donovan followed Tartaglia into the kitchen at the back and dumped the cartons and bags on the black granite counter. The space was clean and modern, all stainless steel and wood, with a pale floor and a round glass table in one corner. It was certainly stylish, but she found it quite cold and clinical, preferring something more homely and rustic like the kitchen she shared with her sister Claire. She glanced out of the window but it was so dark outside and the window so misted with rain, she couldn't see anything of the small back garden.

'What the hell's the matter with him?' Tartaglia said, jerking his head in the direction of the sitting room as he started to rinse the plates and cutlery in the sink.

'He told me earlier this evening that he and Nina have split up.' She dropped the empties into the bin. They had eaten almost everything, apart from some rice and chicken in yellow bean sauce. It was too good to throw away and she left the cartons on the counter in case Tartaglia wanted to keep them.

'She looked perfectly normal to me the other day, what I could see of her.'

'She's the one who's left him. Apparently, she's found someone else.'

'Why am I not surprised?' he said, loading the plates and cutlery into the dishwasher. 'And he'll have problems in spades if he keeps this lark up. Wakeley will have him out on his ear if he catches a whiff of alcohol on his breath. You know what he's like.'

'I'm sure Simon's not drinking during the day.'

Tartaglia gave her a sceptical look and wiped his hands on a tea towel. 'Going out and getting rat-arsed isn't going to solve anything.'

Donovan folded her arms and leaned back against the counter. He could be so black and white at times, as if he never made mistakes, as if he never let his emotions run away with him. But she knew better.

'He still loves her, for Christ's sake. He's hurting. Aren't you in the least bit sympathetic?'

Tartaglia grabbed a cloth from the sink. 'Of course I am,' he said, moving her aside and wiping the counter. 'But getting pissed isn't going to bring Nina back, if that's what he wants.'

'I don't know what he wants but he's so down. Think how awful it must be going back to that flat on his own, with Nina not there, with all the memories.'

Tartaglia rinsed the cloth and hung it over the tap to dry. 'I imagine it's hell, but only he can sort this out.'

He gave her a pointed look. She wondered if he thought she was interfering or if he meant something else. She felt the colour rise to her cheeks. She may have half-fancied Turner in the past but Tartaglia wasn't to know that. Anyway, she had more than enough sense to steer clear of Turner in his current state. What he needed was sympathy and understanding until he found his feet again, although Tartaglia clearly didn't see it that way. Things had always been a little awkward between him and Turner, although she had no idea why. She wondered if it was professional rivalry both strong-headed men of roughly the same age, experience and rank or perhaps it was simply because they were chalk and cheese.

There was a loud clatter from the kitchen door and a scrawny, pale grey Siamese cat appeared through a flap in the bottom panel. It uttered a strange raucous sound and made a beeline for Tartaglia, rubbing itself up against one of his legs as it looked up at him expectantly.

'In a minute, Henry,' Tartaglia said, as if used to it.

'Didn't know you had a cat.' Donovan bent down to stroke it but the cat ignored her, its eyes pinned on Tartaglia.

'I don't. He belongs to the lady upstairs, but he likes to spread himself around.'

'But you have a cat flap.'

'It was put in by the previous owner,' Tartaglia said, moving to the counter and tipping what was left of the chicken in yellow bean sauce onto a plate. 'I just haven't got around to changing it.'

He added the remains of the fried rice and put the dish down on the floor. Henry tucked into it immediately as though he ate Chinese every day.

'Right, we're done.' Tartaglia dumped the cartons in the bin and switched off the light. 'Let's get Simon into a taxi.'

They found Turner curled up on the floor in a foetal position fast asleep amongst the cushions, cuddling one tightly in his arms. His mouth was open and he was snoring.

'I'd better go,' Donovan said, picking up her bag and coat as Tartaglia rescued Turner's glass and the stub of a cigarette from his fingers. 'What shall we do with him?'

Tartaglia sighed. 'Suppose we'd better leave him where he is. Nothing's going to wake him in that state. If he's stiff in the morning, it's his own bloody fault.'

He saw Donovan safely to her car, then came back inside and tidied up as best he could around Turner. Relieved that the floors were wooden and that Turner had somehow missed the rug with his ash, he collected the glasses and ashtray and took them into the kitchen, along with the remains of the bottle of Glenfiddich. He fetched a couple of blankets from the cupboard in the hall and as he draped them over Turner's comatose form, Henry curled himself into a tight knot next to Turner's chest, as though he belonged there. Amused at Henry's perennial fickleness, Tartaglia gazed down at Turner for a moment. Love made fools of even the most rational of people, including himself, and maybe he had been a little insensitive Donovan certainly thought so.

He sensed Turner's desperation and he felt for him. But the man was also a bloody idiot. Was it fair to have married Nina? Had he really loved her? Or was it yet another of Turner's whims, one of his ill thought out, knee-jerk responses to whatever life threw at him? As for Nina, Tartaglia remembered an evening with her not that long before she married Turner, when she had told him about the problems she and Turner were having. Fuelled by wine and the lateness of the hour, she had let down her guard and he had glimpsed the insecurity and neediness beneath. Turner was hardly the man to make her happy, although he hadn't said so for fear of hurting her. He hoped they would be able to work it out between them, but he gave it slim odds.

As he thought of the two of them together with all their wasted emotions and doomed relationship, unaccountably he felt a pang of longing as sharp as the blade of a knife. He looked up at the mantelpiece where he had temporarily placed the black and white photograph of Rachel, retrieved from Steele's office. She stared down at him and he closed his eyes, picturing her as she had once been, teasing, vibrant and full of laughter. He heard her telling Williams about what had happened that night. He imagined her in her dark, mirrored bedroom, taking off her work clothes and getting dressed again to go out, brushing her silky hair, putting on her make-up and perfume and walking down to the bar. He saw her sitting on the stool and ordering herself a martini. As she sipped her drink, she looked into the large mirror, met his gaze and smiled.

He opened his eyes and shook his head at his foolishness. He would never know her. She was lost to him. What he needed was a real flesh-and-blood woman, warm, tangible and responsive, not a ghost.

He was about to switch off the light and go to bed when he remembered what he and Turner had been talking about. He helped himself to the last cigarette from Turner's pack on the floor and sat back down on the sofa with the box containing the crime scene files. He flicked through the divisions until he found a slim folder marked Crime Scene Reconstruction. As he opened it and pulled out a stack of A4 photographs, the first image, the symbolism of the pose now all too familiar to him, made him gasp.

The model representing Catherine Watson was crouched down on her knees, naked, head bent forwards, hair pooling over her face. Her mouth was gagged with a pair of beige tights, which were tied tightly around her head. Her legs were trussed at the knees and ankles with duct tape, and her hands bound in front of her, clasped as if in prayer.