When I was a teenager, growing up in a village near Lewes in East Sussex, I had a friend whose house was very different from everyone else’s. For a start, it had about five times as many bedrooms. It also had tall iron gates, a long, tree-lined driveway and a haunted Minstrel’s Gallery. This place - which I now know to be a Victorian Gothic Manor - looked very grand on the outside, imposing with its tall grey flint walls; but the inside told a different story. The house was in a state of collapse.

My friend’s family was not landed gentry. Far from it. Her father, a drinking man, keen on the races, had won it in a bet. It was crumbling and damp, with rattling casement windows and no heating, and there was no money to fix anything. I got the sense that nobody cared; the family was breaking down and that house was not just physically gloomy, but unhappy and troubled. I felt, instinctively, that it was not just the container of the family’s sorrows, but - somehow, inexplicably - the source of them.

As a teenager, I would go there from time to time and marvel at the grandeur of the tall iron gates and that long driveway; climb the sweeping staircase to what is, in my memory, an endless procession of dark and musty rooms, with damp plasterwork, old quilts, a pervading cold and flitting shadows. Of course, that sense of haunting was thrilling for a teenager. I remember one party - 20 drunk 14-year-olds screaming across the unkempt lawns, only to end up crammed into the (surprisingly tiny) kitchen, too spooked to venture any further into the house.

My friend confided to me once that she sometimes had a ‘visitor’ at night. She would wake in the small hours to find a shrouded old lady sitting on her, pinning her to the mattress. She would be paralysed when this happened, unable to even cry out. This terrifying apparition, she was convinced, meant to choke her.

The friend and I lost touch when I went off to university. Her life, I heard, did not unfold as happily as mine. The family did break up and the Manor was sold. But 30 years on, I found it still lodged in my mind, that huge, neglected flinty beast in its idyllic spot beneath the South Downs. It became a key setting in my novel, the perfect symbol of how a grand and imposing façade can conceal rotten secrets. And my friend’s ‘night visitor’ came to life again in my book.

I still long for the Sussex countryside – the chalk paths up to the South Downs, pheasants panicking across country lanes in the mist, and the beauty of my hometown, Lewes, slotted between the hills. I live in Oxford now, and people tell me I’m lucky but I still dream of moving ‘home’ when the children leave. I did go back to the old Manor while researching my novel. I went up to the iron gates and peeked through, catching a glimpse of grey flints. I thought about going up the drive and knocking on the door, introducing myself, explaining my mission. In the end, I didn’t dare.

Lucy Atkins’s novel, The Night Visitor, is published by Quercus and is available online and from all good booksellers.