This was the year where the supernatural went supernova; the year in which a sense of creeping dread has been positively revelled in. Paranormal Activity became one of the surprise film hits of 2009. The world was captivated by the strange soap opera of a romantic vampire in the latest episode of the Twilight saga, New Moon. And one of the biggest literary thrillers has been Sarah Waters' chilling ghost story The Little Stranger. "
After a year in which she was placed on the shortlist for the Mann Booker Prize alongside AS Byatt and the eventual winner Hilary Mantel, the author - whose previous works include Tipping the Velvet, Affinity, Fingersmith and The Night Watch - is finally able to take a step back and really comprehend her successes. "Until recently I couldn't even imagine writing another book," she says. "I don't think I anticipated how open to interpretation The Little Stranger would be. Everyone seems to read it in a slightly different way, which hasn't really been the case for my other novels. That's hugely exciting, but it does bring with it some downsides: I have been talking about it a lot, and it's still there... in my head."
Of course, such open-endedness is The Little Stranger's real strength. It begins in classic ghost-story fashion: the narrator is a 1940s doctor called Faraday, who visits Hundreds Hall, a crumbling country house in which weeds force themselves through stones, darkened rooms are blocked off and an all-round spooky air pervades. Waters' triumph is in creating an immediate sense of unease and intrigue, heightened by the strange noises and unexplained illnesses.
Although Faraday treats the ailments of Roderick Ayres, the master of the house, the RAF veteran steadily succumbs to what are written off as symptoms of post-war "nervousness". But are they something more sinister? Roderick's sister Caroline is plain and graceless, but Faraday finds himself increasingly attracted to her, and to this family, as he seeks to find rational explanations for the strange events at the house. Waters' greatest success is that The Little Stranger becomes more than a ghost story. It is also a love story and a picture of a post-war Britain unsure of its future.
"I found myself happy to invoke the ghost-story genre," Waters says. "I mean, when you're writing about a big old haunted house it's hard not to recall books such as Daphne du Maurier's Rebecca or Henry James' The Turn Of the Screw. The whole tradition of writing in that way is full of echoes. The haunted houses look like each other, and the narratives resemble the books that preceded them." The conversation is sidetracked briefly by, of all things, the colour of the peeling wallpaper in one of Hundreds Hall's many rooms. It's yellow - very deliberately invoking Charlotte Perkins Gilman's famous 19th-century psychological drama The Yellow Wallpaper.
"I could have resisted all those links but I was happy to go along with them," she adds. "But that was because I felt I was bringing something new to the genre too. I was using it to talk about class, because it's a story about a Britain that was very definitely changing during that post-war time, too. The haunted house symbolises all that I think, so it was a new element for an old format." Dr Faraday represents this class collision more than most. Born to poor parents who, he often regrets, sacrificed everything for his education, he is pessimistic about his role in the forthcoming National Health Service. His mother also used to work as a servant in Hundreds Hall, which causes huge embarrassment for both him and the Ayres family.
He bears the mental scars of class struggle - many of his old school friends simply work the fields and factories - and becomes more and more obsessed with Hundreds Hall and the possibilities it might hold for his own future. Waters' trick is to change, almost imperceptibly, the reader's relationship with this narrator. His scepticism about a malevolent presence is shared at the beginning, but slowly Faraday's ulterior motives to live there himself become overwhelmingly clear as he blindly attributes the various breakdowns suffered by the house's inhabitants to simple "tiredness".
"He is, ultimately, an unreliable narrator - although not in the sense that he or I are out to deliberately deceive anyone," Waters says. "There are things that we can see going on that he can't or won't acknowledge. The force of his own desires to live in the house and the strength of his own class resentment - the feeling that he will have 'made it' if he lives there - play a huge role in what happens there.
"He did, for me, become a much more sinister figure by the end. But it's funny. Some people read him as being this nice doctor who other people are just cruel to. And yet others have reacted completely violently against him, seeing him as manipulative and unpleasant. I even had people ask whether he's deliberately dull and unlikeable! But I liked him a lot. He's not dull, he's ordinary. An ordinary man trying to talk about extraordinary things."
The most extraordinary aspect of The Little Stranger is how open to interpretation it is, but many readers will end up realising that class haunts its characters more than any ghost. It's not a book that expects anyone to feel sorry for the post-war gentry, but it does reveal a social stratum that was forced to sell off vast tracts of its history to survive. "A lot of people saw Labour's electoral success just after the end of the Second World War was quite a big blow," Waters explains. "It was an extraordinary moment in British social history which I'd done a lot of research into for The Night Watch. I found myself still drawn to that post-war world, that sense that the mother in the hall has of not being able to detach herself from the history of where she lived.
"People like her did feel haunted by their past, I think. The hall was very real to her, but she can also see it slipping away. So part of what made writing The Little Stranger so straightforward is that, for me, it was completely rooted in that historical moment - but once you're in the house it's also dislocated from history. Because the things that happen are timeless haunted-house things." Or are they? There are strange noises and weird inscriptions that appear on walls. People are driven mad by what they think they can see. But, as her previous books prove, Sarah Waters isn't a supernatural fiction writer. This is not a straightforward ghost story with an exorcism at the end to tie everything up.
"I really tried to write it in a way that if you want to believe there is no ghost in The Little Stranger at all, you can," she says. "The ending is about as unresolved as I could get away with, which I know has frustrated some people, but for me it had to be that way. "It's not a case of not being interested in straightforward ghost fiction. It's that I think, mainly, ghost stories fit into Gothic fiction. One of the things I've always liked about the great Gothic novels is that they are tales of psychology. It's not a coincidence that we use terms in everyday life such as being 'haunted' by something, or being 'confronted by our demons'. We borrow the language of terror to talk about our own psychological processes. And for me, all the characters in the novel are haunted by their own disappointments or anxieties. The house just brings them all together in a big simmering pot."
Waters stirs that pot expertly. Such a cracking, unsettling read deserved its place on the Booker shortlist. Indeed, the eventual winner of the prize, Hilary Mantel, called The Little Stranger "gripping, confident, unnerving and supremely entertaining". This entertainment often comes from trying to work out exactly what Hundreds Hall's malevolent spirit is. Waters has already said that readers could believe there is no ghost at all, but the sense that she really enjoyed creating the strange atmosphere of this haunted house doesn't quite back that up. Is she prepared to give away what this apparition is, though? Not quite.
"I loved writing this book and there is definitely something... supernatural going on at Hundreds Hall" she says. "But that doesn't mean I believe in the supernatural myself. I've certainly never experienced anything personally that feels like that. I don't think that matters, though. What's important is that I'm fascinated by our yearning for the supernatural. The human brain can produce some very odd subtexts to things, which is perhaps where these visions come from. I was really attracted to that as an idea, and always have been."
Interestingly, Waters says that ghost story she tells so expertly was initially based on a famous 1948 detective novel by Josephine Tey called The Franchise Affair. The territory is similar - a post-war anxiety about class - and Betty, one of the characters in Waters' book, is named after the focus of Tey's story. In fact it is through her that The Little Stranger's sense of unease is first established.
"And in classic thriller fashion, no one will listen to her," Waters says. "I was intrigued by The Franchise Affair. The sense of history it has is something I'm very interested in." So does this make Waters, like Mantel or Robert Harris, one of those fashionable writers: a historical novelist attempting to say something about our current world? This question stops Waters in her tracks. "I don't think so, no," she says after a long pause. "I'm just interested in the past. I really do want to go back to a specific period and think deeply about what was happening then. There are always parallels, but they're unintentional. They're certainly coincidental: at a time when we're conscious of big historical forces at work in the world, maybe it's obvious that we're going to enjoy fiction that's centred on other periods of history where there were similar collisions."
Whether Waters will remain a historical novelist herself remains to be seen. As she gets back to work on a new novel, it seems the experience of creating a ghost story in her own inimitable way has crystallised why she writes, but not necessarily what period she writes about. "I'm interested purely in stories and storytelling," she says. "Maybe that means one day I'll write a novel which has a contemporary setting, maybe not. It's finding my particular way to do it that's important."
The Little Stranger (Little, Brown) is out now.