'Who could? I'm in the property services department – Frances Baring.' She frowned into the mirror of her compact, stung by the rebuff and irritated with herself for having to approach me so clumsily. 'Please, Mr Sinclair. I need to talk to you about an old friend of ours.'

As the waiter took our order she tore a sachet of salt and poured the grains into the ashtray. She twisted the paper square into an arrow and pointed it at me.

Still unsure why this attractive but prickly woman had approached me, I said: 'We're neighbours – I saw you this afternoon at Eden-Olympia.'

'Alcatraz-sur-Mer.'

'Where?'

'Catch up. It's my nickname for Eden-Olympia.'

'Not bad. But is it a prison?'

'Of course. It pretends to be a space station. People like Pascal Zander are really living on Mars.'

I stopped her mutilating a second sachet. ' Frances, relax. Our drinks are coming.'

'Sorry.' She flashed a quick smile. 'I hate this kind of thing. I'd never have made a good whore. I could cope with the sex, but all those smoky glances across crowded lobbies… I wanted to talk to you, away from Eden-Olympia. I'm due to see your wife soon, I believe.'

'Jane?'

'Yes. One of the endless check-ups Eden-Olympia arranges. When they find nothing wrong you love them all the more. I look forward to meeting her.'

'She helps out with colonoscopies.'

'You mean she'll put a camera up my bottom? I've always wanted to be on television. What about you?'

'I'm on holiday. It's lasted a little longer than I planned.'

'We've all noticed. You're the Ben Gunn of our treasure island. I thought you were writing a social history of the car park.'

'I should. It's like Los Angeles, the car parks tend to find you, wherever you are. My legs need the exercise – they're getting over a flying accident.'

'Yes, you're a pilot…' She lit a cigarette, briefly setting fire to the ashtray. 'Does that mean you have an interesting sex life?'

'I hope so – I'm a devoted husband. That must strike you as totally deviant.'

'No. Just a little against nature. Rather romantic, though.'

Tired of this forced banter, I waved away the cigarette smoke and tried to meet her eyes. Was she holding me here until Zander's men arrived? A team could have followed Delage's limousine to Cannes, tipped off by the aide, then lost me as I zigzagged on my abortive errands. Frances Baring had picked up the trail as I wandered along the Croisette.

But if she was a femme fatale she was a surprisingly inept one, working on her own with only the roughest idea of how to pursue her agenda. I was struck by how much she differed from Jane. My teenage doctor was girlish but supremely confident, while Frances was sophisticated but unsure of herself, probably climbing the upper slopes of the corporate pyramid with little more than her scatty humour to protect her. I looked over the balcony at the orthopaedic mannequins wearing their fetishist armour. Jane would break down in guffaws if I suggested that she wore one of the cuirasses as an erotic aid, but I could imagine Frances harnessing up without comment.

Seeing me smile at her, she sipped her drink and then held the glass between us, exposing the waxy imprint of her lips like the forensic trace of a kiss, the second I had seen that day.

'Right, Paul,' she announced. 'I'm relaxed.'

'Good. Now, who is the friend we share? Friendship isn't that common at Eden-Olympia.'

'This friend isn't there any more.' Her fingers moved towards a salt sachet, stopped and calmed themselves by eviscerating the stub of her cigarette. 'He died a few months ago. Last May, in fact…'

'David Greenwood?' When she nodded, her face clouding, I said: 'How long have you been at Eden-Olympia?'

'Three years. It feels longer since David died.'

'You were close?'

'On and off. He was very busy.'

'The children's refuge, the methadone clinic. And the Alice library.'

' Alice, yes. "Never seen by waking eyes…"' She stared at the imprint on her glass, unaware that her lips were moving, a sub-vocal message across the void.

Concerned for her, I reached out and steadied her hands. 'Were you there on May 28?'

'In my office at the Siemens building. I was there all day.'

'You saw the police arrive and heard the shooting?'

'Absolutely. Helicopters, ambulances, film crews… the whole nightmare played itself out like an insane video game. I haven't really woken up.'

'I understand.' I held her empty glass, hot from the fever of her hands. 'All those deaths. They hardly seem possible.'

'Why?' She frowned at me, assuming that I was making some abstruse point. 'Everything's possible at Eden-Olympia. That's its raison d'être.'

'But the murders don't chime with Greenwood 's character. He was a builder, a creator of projects, not a destroyer. Jane says he was an old-style idealist.'

'Maybe that explains it all – idealists can be dangerous.'

'You're saying he shot all those people from some higher motive?'

'What other reason is there? A sudden "brainstorm"?'

'It seems likely.'

'Eden-Olympia is a brainstorm.' She spoke with soft disgust. 'Wilder Penrose is storming the brains…'

'I take it you don't like the place?'

'I love it.' She signalled to the waiter, ordering another round of drinks. 'I make three times the salary I did in London, there are perks galore, a gorgeous flat at Marina Baie des Anges. And all the games I want to play.'

'Are there any games? The sports clubs are empty.'

'Not that sort of game.' She watched me with the first real curiosity, her eyes running over my tweed sports jacket. 'These are games of a different night.'

'They sound like quite an effort.'

'They are. Games at Eden-Olympia are always the serious kind.'

'The man who gave me a lift to Cannes seemed to be saying that.'

'Alain Delage? Be careful with him. He looks like a mousy accountant but he's a textbook anal-sadist.'

'You must know him well. Were you lovers?'

'I don't think so. His wife is more my type but she plays hard to get. That's the trouble with Eden-Olympia – you can't remember if you once had sex with someone. Like Marbella or… Maida Vale.'

She had tossed in my London address, a friendly warning that she knew more about me than I assumed. But I was sure now that Frances Baring was not working for Zander or anyone else at Eden-Olympia. For reasons of her own she had set up our accidental encounter, and was now pretending to flirt with me, unsure whether I was worth the effort. In her edgy way, nervous of being rebuffed, she was reaching out to me. I sensed that she needed my help, but would take her time in coming to the point.

Already I had warmed to her, to the tart tongue and wary eyes, to the full figure she casually used to keep the waiters in their place. At last I had met someone who was a direct link to David Greenwood and not afraid to speak her mind.

'You wanted to talk about Greenwood,' I reminded her. 'How well did you know him?'

'We met at official functions, topping-out ceremonies. He was lonely and didn't realize it. But you understand how that feels.'

'Am I lonely?'

'Limping around all day?' She brushed her cigarette ash from my sleeve, and seemed almost concerned for me. 'Poor man, I've watched you.'

' Frances… could someone else have carried out the killings? Suppose David was framed. A young English doctor…'

'No.' Her eyes roamed around the bar, in search of another drink, but she spoke distinctly. 'David killed them – seven of them, anyway.'

'And the hostages?'

'I doubt it. Not much point.'

'The Cannes police say they were shot in the garage. Everyone accepts that, like the brainstorm explanation.'

'It's the perfect alibi.' She lowered her voice as two elderly American surgeons in tracksuits sat at the next table. 'But it only just worked. David Greenwood nearly destroyed Eden-Olympia. Huge amounts of corporate funding were pulled out. We had to renegotiate leases, cut rents and offer rebates that were practically bribes. Who cares about a couple of dead chauffeurs?'