'Right – Miguel will let us in. He looks after the place, or what's left of it. The housekeeper and her husband have gone. They simply couldn't cope.' Hennessy waited for the gates to open. 'It's quite a spectacle, I must say…'

'What about the chauffeur – do I tell him that I'm Frank's brother? He may 'No. He liked Frank, sometimes they went scuba-diving together. He was very upset when Frank pleaded guilty. As we all were, needless to say.'

We entered the gates and rolled on to the thick gravel. The drive rose past a series of terraced gardens filled with miniature cycads, bougainvillea and frangipani. Sprinkler hoses ran across the hillside like the vessels of a dead blood system. Every leaf and flower was covered with white ash that bathed the derelict property in an almost sepulchral light. Footprints marked the ashy surface of the tennis court, as if a solitary player had waited after a brief snowfall for an absent opponent.

A marble terrace ran along the seaward frontage of the house, scattered with roof-tiles and charred sections of wooden gabling. Potted plants still bloomed among the overturned chairs and trestle tables. A large rectangular swimming pool sat like an ornamental reservoir beside the terrace, constructed in the 1920s, so Hennessy told me, to suit the tastes of the Andalucian tycoon who had bought the mansion. Marble pilasters supported the podium of the diving board, and each of the gargoyle spouts was a pair of carved stone hands that clasped an openmouthed fish. The filter system was silent, and the surface of the pool was covered with waterlogged timbers, floating wine bottles and paper cups, and a single empty ice-bucket.

Hennessy parked the car under a canopy of eucalyptus trees whose upper branches had been burned to blackened brooms. A young Spaniard with a sombre face climbed the steps from the pool, gazing at the devastation around him as if seeing it for the first time. I expected him to approach us, but he remained thirty feet away, staring at me stonily.

'Miguel, the Hollingers' chauffeur,' Hennessy murmured. 'He lives in the flat below the pool. A little tact might be in order if you ask any questions. The police gave him a hell of a time.'

'Was he a suspect?'

'Who wasn't? Poor chap, his whole world literally fell in on him.'

Hennessy took off his hat and fanned himself as he gazed at the house. He seemed impressed by the scale of the disaster but otherwise unmoved, like an insurance assessor surveying a burned-out factory. He pointed to the yellow police tapes that sealed the embossed oak doors.

'Inspector Cabrera doesn't want anyone sifting through the evidence, though God only knows what's left. There's a side door off the terrace we can look through. It's too dangerous to go inside the place.'

I stepped over the shattered tiles and wine glasses at my feet. The intense heat had driven a jagged fissure through the stone walls, the scar of a lightning bolt that had condemned the property to the flames. Hennessy led the way towards a loose French door levered off its hinges by the firemen. Wind gusted across the terrace, and a cloud of white ash swirled around us like milled bone, restlessly hunting the air.

Hennessy pushed back the door and beckoned me towards him, smiling in a thin way like a guide at a black museum. A high-ceilinged drawing room looked out over the sea on either side of the peninsula. In the dim light I found myself standing in a marine world, the silt-covered state-room of a sunken liner. The Empire furniture and brocaded curtains, the tapestries and Chinese carpets were the decor of a drowned realm, drenched by the water that had poured through the collapsed ceiling. The dining room lay beyond the interior doors, where an oak table carried a pile of laths and plaster and the crystal debris of a chandelier.

I stepped from the parquet flooring on to the carpet, and found my shoes sinking as the water welled from the sodden fabric. Giving up, I returned to the terrace, where Hennessy was gazing at the sunlit peninsula.

'It's hard to believe one man started this fire,' I told him. 'Frank or anyone else. The place is completely gutted.'

'I agree.' Hennessy glanced at his watch, already keen to leave. 'Of course, this is a very old house. A single match would have set it going.'

The sounds of a tennis game echoed from a nearby court. A mile away I could make out the players at the Club Nautico, a glimmer of whites through the haze.

'Where were the Hollingers found? I'm surprised they didn't run on to the terrace when the fire started.'

'Sadly, they were upstairs at the time.' Hennessy pointed to the blackened windows below the roof. 'He was in the bathroom next to his study. She was in another of the bedrooms.'

'This was when? About seven o'clock in the evening? What were they doing there?'

'Who can say? He was probably working on his memoirs. She might have been dressing for dinner. I'm sure they tried to escape, but the intense blaze and the ether fumes must have driven them back.'

I sniffed at the damp air, trying to catch a scent of the hospital corridors of my childhood, when I had visited my mother in the American clinic at Riyadh. The air in the drawing room carried the mould-like odours of a herb garden after a rain shower.

'Ether…? There's something curious about that. Hospitals don't use ether any more. Where was Frank supposed to have bought all this bottled ether?'

Hennessy had moved away, watching me from a distance as if he had realized for the first time that I was a murderer's brother. Behind him Miguel stood among the overturned tables. Together they seemed like figures in a dream-play, trying to remind me of memories I could never recover.

'Ether?' Hennessy pondered this, moving aside a broken glass with one shoe. 'Yes. I suppose it does have industrial uses. Isn't it a good solvent? It must be available at specialist laboratories.'

'But why not use pure petrol? Or lighter fuel for that matter? No one would ever trace the stuff. I take it Cabrera tracked down the lab that's supposed to have sold this ether to Frank?'

'Perhaps, but I somehow doubt it. After all, your brother pleaded guilty.' Hennessy searched for his car keys. 'Charles, I think we ought to leave. You must find this a dreadful strain.'

'I'm fine. I'm glad you brought me here.' I pressed my hands against the stone balustrade, trying to feel the heat of the fire. 'Tell me about the others – the maid and the niece. There was a male secretary?'

'Roger Sansom, yes. Decent fellow, he'd been with them for years – almost a son.'

'Where were they found?'

'On the first floor. They were all in their bedrooms.'

'Isn't that a little odd? The fire started on the ground floor. You'd expect them to climb out through the windows. It's not that long a jump.'

'The windows would have been closed. The entire house was air-conditioned.' Hennessy tried to steer me across the terrace, a curator at closing time ushering a last visitor to the exit. 'We're all concerned for Frank, and absolutely mystified by the whole tragic business. But try to use a little imagination.'

'I'm probably using too much… I assume they were all identified?'

'With some difficulty. Dental records, I suppose, though I don't think either of the Hollingers had any teeth. Perhaps there are clues in the jawbone.'

'What were the Hollingers like? They were both in their seventies?'

'He was seventy-five. She was quite a bit younger. Late sixties, I imagine.' Hennessy smiled to himself, as if fondly remembering a choice wine. 'Good-looking woman, in an actressy way, though a little too ladylike for me.'

'And they came here twenty years ago? Estrella de Mar must have been very different then.'

'There was nothing to see, just bare hillsides and a few old vines. A collection of fishermen's shacks and a small bar. Hollinger bought the house from a Spanish property developer he worked with. Believe me, it was a beautiful place.'