I tried to ignore the hammer beat in my throat, tried to convince myself that I wasn't nervous, that there was nothing to be nervous of. I hadn't expected to come this far; but Carlee, a thirster-after new experience, was keen to press on.

I turned and looked behind us. "Maybe we should go back the way we came," I suggested, my voice affecting a casualness I barely felt.

"Aw, that would be a shame. Didn't you say this road loops all the way round to the start again?"

"At Creggan Hill, yes, but it's not that pretty further on. It goes through some farms and stuff, not as nice as Margaret's Walk."

"Through the farms? Cool. Can I get to see the cows close up? And the pigs? Oink oink." Carlee was a bundle of enthusiasm, a restless spirit in search of adventure, which was why I loved her. She had a photographic memory and was constantly seeking out new information, new ways to stimulate her mind. Her excitement was infectious and as I watched her skip up the path I smiled and relaxed. She was wearing light blue jeans, tight and sculpted to her body. Her short bomber jacket was zipped securely, the elasticated hem resting snugly around her waist. From behind, the curve of her buttocks and thighs was mesmerising, a sinuous, rolling vision of beauty, round and undulating, ceaselessly perfect.

It was Carlee who spotted them first, resting on a redundant fence pole. The fence had long since collapsed to the ground, where grasses and creeping rhododendrons were snaked around it, slowly dragging the rusted wires into the obscurity of the undergrowth, and the pole, rotten and creaking, stood incongruously alone by the side of the path. But resting on the top was a delightful posy of wild flowers, freshly picked and vivid in contrast to the dulled wood of the pole.

"They're gorgeous," said Carlee, bending and picking them up. "What are they?"

There were cornflowers, blue, yellow and red; a late flowering, delicate agrimony, slender and fragrant; a perfect, blue chicory and counterpointing dandelion - the beautiful and the rustic - and the sweetest little cyclamen, dainty purple flecks gathered round the base of its pink flowers - all of them neatly gathered and beautifully combined. They were among the final flowerings of the season, small and fragile, a last, brave salute of colour before the creep of winter.

"I wonder who left them?" she said, replacing them lightly on the pole. I had wondered that too. They had clearly been picked very recently, but there was nobody in sight, and we had encountered no-one for at least half an hour.

The path began to track upwards, climbing steadily as it approached a sharp corner. Rising above us, twenty-five feet high and obliterating the view, was the steep, man-made banking of a disused railway line. The graceless bank obscured the sun and the north facing corner in which we found ourselves was perennially damp and cold, blanketed by coarse, ugly shrubbery. Even on the brightest day there was a gloom about the place, a dull, listless air in which even the light seemed tarnished. I felt a sense of apprehension once more and sought Carlee's hand in reassurance. Ahead of us was a tunnel through the bank, a dark and echoing passage with graffiti-lined walls and discarded beer cans and the odour of piss and staleness. As we marched through our footsteps thrummed low and incessant, bouncing off the walls and back again and back once more, moments in the immediate past being relived in sound, time circling round itself in a confused cacophony. Carlee laughed, and her sweet tones swirled through the expanse, swooping towards us time and again before finally dimming and flying into history.

"Carlee!" she shouted, and her name called back, over and over, an instant in time repeating itself continuously. "Carlee! Carlee! Carlee." The tunnel was filled with noise, with a hundred, a thousand shouts for Carlee, emanating from every corner, layered one on the other like an elaborate multi-part harmony, reverberating in the air, resounding, calling, assailing our ears, before gradually dying off, becoming muted, hushed, until they fell, at length, into a single plaintive appeal: "..Carlee, 3;lee, 3;lee." And then, nothing. And we stood, listening to the echoing silence, to the noiseless passage of time.

"I always said you Americans were loud," I laughed.

"Don't you know it, babe? And don't you love it?"

We stepped through the tunnel and instantly felt the blush of daylight on our faces. It may have been the brittlest October sun, but the contrast with the chill of the dark tunnel was striking: it was only in the relative warmth of the sun that I realised how cold I was, and I shivered involuntarily.

"You okay, babe?"

I nodded, smiling, but I was tense. Because, there in front of us, was a sight I never expected to see again.

The Ripley house.

I held my breath and gripped Carlee's hand firmly as we walked towards it. Carlee hadn't spotted it yet and walked on unhurriedly. My mind was spinning, trying to control the fluctuating emotions which the sight of the Ripley house had triggered in me.

Finally, Carlee spotted it.

"Hey," she shouted, freeing herself from my grip and running towards it, "a ruin! What is it?"

Not just a ruin, I thought, not just a ruin. This is the Ripley house, the scene of a thousand childhood nightmares.

"It's called the Ripley house," I said. "Been derelict for about forty years. It scares the shit out of me - always has."

"Why? It's just a ruin. It's not haunted, is it?"

"Don't even joke about it, Carlee. I mean it: it scares the shit out of me."

Carlee turned as she heard the obvious distress in my voice. Her hazel eyes stared at me solicitously.

"Hey, sorry babes, didn't mean to scare you."

"It's okay," I replied, feeling foolish. She was right. It was just a ruin, a heap of stones gradually being reclaimed by nature. Whatever childhood terrors it had held for me ought now to be banished, along with those other immature fears - dogs, the dark - which had played on the timidity of my younger self. I forced myself forward.

The Ripley house had been burned down in the sixties. No-one knows how the fire started, but once it took hold it quickly gripped the entire house. Being so far from town, situated alone in the woods down the long, winding Creggan Road, it was some time before the alarm was raised, and by the time the fire fighters had made it to the scene the house was ablaze, flames spuming out of every window and seething across the roof. The water supply, high enough to serve the needs of one family, was insufficient to service the fire engine hoses: they dribbled ineffectively against the advancing tide of flames. Within an hour, the building was a ruined shell.

And inside it lay the bodies of Mary Ripley and her one year old daughter Aileen.

Fanciful stories circulated about what happened that night: some said it was arson, that Ripley himself set the house alight, or that it was kids having a lark, or a mysterious stranger who was reported to have been seen watching the house. Ripley, others said, went mad and died within a month, grief stricken and inconsolable. Some said that Mary and Aileen perished in their beds, overcome by fumes, while more lurid versions had Mary screaming from an upstairs window and throwing her baby out to instant death rather than have it face the slow, agonising lick of consuming fire.

But the truth is no-one knows what happened that night.

I stood at the remains of the front door and looked in. There wasn't much left of the place now - even less than the last time I had been here. The outside walls were mostly gone, just a few fragments of the foundations poking up from the earth, marking the boundaries of the fated house. In places, a few stones remained stubbornly locked together, last vestiges of the original wall standing resolutely in the face of time. I often wondered about those stones, wondered why they had held fast while the others around them had collapsed: did the builders know, when they were erecting the house, when they were handling those very stones, that they were special, more robust than the others, that they would outlive their time? Did they know that those stones would end their time a bridge between generations, marking a place of tragedy?

I stepped into what would have been a tiny lobby. My heart was thumping, but it wasn't fear I felt now. The Ripley house had taken me over again, as it always did, as it always had, as it always would. It was pity I felt, and regret and shame, a heaving, heavy sweep of sadness which overwhelmed my senses, engulfing me in a blanket of melancholy. The years rolled by and the memories returned: the fears of my childhood, the empathetic ache in my heart, the feeling that I was, somehow, connected.

And also those other memories, the later ones, the ones best left untouched.

The internal walls were better preserved, rising seven feet high in the central column where the fireplaces had been. I walked into the living room, cursing the tear which had rolled down my cheek. Carlee stepped over one of the foundation walls to join me and I frowned at her: I knew it made no sense, but it still felt disrespectful not to use the front door. I looked at the wall, at the fireplace, at what would have been a homely hearth, while Carlee clasped my hand. In contrast to hers, mine was icy cold.

"What happened here?" she asked.

And I told her, as well as I could, as much as I knew.

"Poor kid," she said, when I told her of Aileen. "What a way to die."

What a way to die.

It happened the year I was born, but we lived in a small town, parochial and uneventful, and the Ripley House was still a cause célèbre as I grew up. Schoolchildren relished the myth of the house, delighted in inventing graphic interpretations of what might have happened and in recreating those tragic events. We would go down there, Roger and Margot and Eilidh and I, teasing and frightening one another, garnering collective bravery from the aggregation of our individual fears.

"They say they never found the bodies," Roger Watters would say. "Bones are still there, buried in the ground." And we would look for them, ridiculously searching through the scrubby grass which had grown over the site, looking for bones, for clues, for relics of the past.

But I never felt comfortable doing that, and after a while I dropped out. It seemed to me a desecration of a moment of sorrow: this wasn't a place for the living. It didn't stop me visiting the Ripley house, but I chose to go alone, embarking on solemn pilgrimages and standing in the living room, just as I was doing now, and stoking my imagination, putting myself into the house, willing myself to conjure what it must have been like to live there.

And in that way I grew to love the Ripley house as much as I feared it.

I would stand, my fifteen year old self, intense and sensitive, and stare into the fireplace, imagining the sensuous rippling of a winter fire, the crackle of logs, sparks and lances of flame licking up the chimney in a sensuous, pulsating dance. There would be a big coal bucket, functional and plain, and a heavy rug by the hearth. I tried to see the walls, imagine what paper they would have had, what pictures would have hung, and guessed at the colour of the carpets, the ceilings, the furniture. By plotting the progress of the sun through the afternoon, I would try to establish where they would have placed their furniture. Here, at the very spot where I stood, this was where I thought Mr Ripley's chair would have been, close enough to the fire for him to reach it with a poker, but with the low sun filtering through the window onto his cheek in the long summer evenings. I would will myself into the scene, look for ways into the past, invite myself to a time and a place, a world and a life not my own.

But I never could break through.

Not until that day. The last time I had set foot in the Ripley House.

I knelt down and drew my hand over the soft, dewy blanket of grass and closed my eyes.

Oh, Hallow Road confess your soul,

Reveal your secret, swear parole.

Unburied past, unbearing fate

Unblinking crime:

At Ripley's house I hesitate

Adrift in time 3;

Adrift in time. Rootless and hopeless, the shock of what happened here too intense to be buried in the past, too raw to be assuaged by the future, a moment and an event transcending time.

I was aware of a rustle in the beech trees behind and the air fell chill. It was no darker than it had been a moment before, but it felt as though a shadow had descended over me. A faint dizziness swept through me and I listed to the side, resting heavily on my palm to keep my balance. A sheet of panic iced across my forehead as I felt the first twinges of that long forgotten, much reviled sensation begin to creep through me. Just once this had happened to me, just once: and it happened that day, that last day.

And I didn't want it to happen again.

I got to my feet, my mouth dry and nausea rising in my throat, and I looked round for Carlee. We had to get out, we had to get away from the Ripley house before we were engulfed.

But Carlee was nowhere to be seen.

And, anyway, I knew it was too late.

The world began to slide away from me, a vaulting, vertiginous swoop into chaos as greens merged with browns, lights with darks, air with earth and life with time. I felt as though I were pirouetting madly through space, edging slowly towards reality as it hurtled unheedingly at me. My eyes were open but I couldn't see, nor could I hear, nor smell, nor touch. I trembled, alone and unconnected, as the world melted and warped before me. Fixing my gaze on one of the foundation stones, I tried to anchor myself, but time's axis tilted once more and I watched aghast as the stone appeared to replicate itself, shimmering in front of me, intractable and impossible. And then again, and again, and as I looked on, paralysed, the wall of the house began to emerge from the dust of time and re-form in front of me. Stone by stone, inch by inch, the walls were resurrected - while all around was the chill of nothingness, the silence of death. Moment by moment, day by day, the scene was transported, time transcended.

Until.

I found myself in the Ripley house. In Ripley's living room. Looking through Ripley's window.

Into Ripley's world.

And alone stood I.