The Little Stranger was inspired by a recurring nightmare featuring a spectral figure at the foot of your bed. What motivated you to turn this chilling dream into a work of fiction? Have you had other dreams that have inspired your writing?

Ha! Yes, I still quite often have these ‘night terrors’, waking up with a horrible start and seeming to glimpse a female figure (it’s always female) glaring at me from the end of the bed, or actually looming over me, Woman in Black-style… I remembered these when I was in the early stages of planning The Little Stranger: at that point it wasn’t a supernatural novel at all, but I suddenly thought, hang on, what would happen if I made this a ghost story? And the whole thing sprang to life for me, right then. A lovely moment.

While you are known for your historical fiction, The Little Stranger was your first real foray into the Gothic genre. What prompted this shift and were you inspired by any Gothic novels in particular?

Well, The Little Stranger was my first novel with a full-blown supernatural element, but two of my earlier books – Affinity and Fingersmith – have their Gothic elements, so I do think of myself as quite a Gothic writer, actually. Henry James’s The Turn of the Screw and Shirley Jackson’s The Haunting of Hill House were both influences on The Little Stranger – as were their brilliant film adaptations, Jack Clayton’s The Innocents (1961) and Robert Wise’s The Haunting (1963).

The novel unfolds in the 1940s, during a period of considerable social change in England. Was it your aim to create a ghost story that would also serve as a social commentary on the class structures of that era?

Yes, definitely. The class changes were my starting point. In fact, I’d realised what a big deal they were in the post-war period, with working-class people coming out of the war with a new energy, a new optimism, and snobbish middle- and upper-class people feeling gloomy and frightened about what they saw as the advent of a dreary new meritocracy – the ‘age of Hooper’, as Waugh has it in Brideshead Revisited. In The Little Stranger, I used a poltergeist to give that gloom and fear a tangible form.

The Little Stranger is notable for its unsettling ambiguity and unanswered questions. When writing the book was it always your intention to leave the ending open to interpretation?

Well, the novel’s narrator, Dr Faraday, is rather unreliable – not in the sense that he’s telling us lies, but in the sense that there are things going on in the story that he can’t or won’t acknowledge. So you have to read between the lines a bit – and I tried to make the ending as ambiguous as I felt I could get away with, without actually frustrating readers. I do give quite a lot of hints, however.

Tell us about a book that made you want to become a writer. How did it inspire you to embark on your own creative journey, and how did it influence your writing style or aspirations as an author?

I think it was Philippa Gregory’s Wideacre trilogy, which I read in the early 1990s. The books are glorious melodrama, outrageously rompy, fantastic page-turners – but they’re also historically astute and thoroughly feminist, really clever about women and power. That combination of scholarship and romp really appealed to me. I thought if I could write something that straddled those two fields – and had a lesbian agenda, too – I would die happy.

Tell us about a book that made you fall in love with reading. In what ways did it shape you, or your worldview, perhaps as a teenager or young adult?

I read Angela Carter’s collection of rewritten fairy tales, The Bloody Chamber, when I was seventeen, and it blew me away. It’s Gothic, feminist, sexy, witty, makes these amazing swoops between high and popular culture – I’d just never seen anything like it. It got right to the quick of me – is still there, in fact.

Is there a book that changed the way you think about the novel, a book that made you reassess what’s possible when it comes to writing fiction, or that broadened your own horizons as a writer?

Jeannette Winterson’s The Passion and Alan Hollinghurst’s The Swimming-Pool Library. I read them years before I thought of writing novels of my own, but the fact that they were both unashamedly queer and unapologetically literary – published by big-name publishers, rather than small, community ones – had a huge impact on me. They taught me that queer fiction could be clever and ambitious while still being sexy and romantic.

Which book are you currently reading, and what made you pick it up?

I’m reading Hanya Yanagihara’s latest novel, To Paradise. What really made me pick it up, to be honest, is its gorgeous paperback cover. But also, I’ve loved her previous books – and this one, like them, is brilliantly strange, engaging and provocative.

Is there a book that you return to time and time again – an older work or classic that you’ve read on multiple occasions? What makes you keep going back to it? Do you find different things in it each time?

The only books I repeatedly reread are Daphne du Maurier’s Rebecca and Patricia Highsmith’s The Talented Mr Ripley. And yes, I always find something new in them. Rebecca is awfully purple at times and, narrative-wise, it’s a bit baggy, but it’s terrific at capturing female interiority. And The Talented Mr Ripley is such a masterpiece of storytelling, and always much more economical than I remember: I just pore over it, thinking, how does Highsmith do this?

Lastly, could you recommend some of your favourite ghost stories for readers to enjoy in the run-up to Halloween?

Oh, there are lots. Elizabeth Bowen’s short story ‘The Demon Lover’, Margaret Oliphant’s The Open Door, Oliver Onions’s The Beckoning Fair One… And for a fabulously uncomfortable read I recommend the short stories of Robert Aickman – for example, ‘Ringing the Changes’, in which a honeymooning couple get caught up in a dark East Anglian ritual that brings the dead back from their graves for a single night, while gleeful locals chant in the streets. ‘The living and the dead dance together. Now’s the time. Now’s the place. Now’s the weather…’