This debut novel by English author Poppy Adams has almost all the elements of a campy horror novel. Crumbling mansion in the English countryside - check. Socially awkward spinster living alone - check. Insects - check.

The only thing it lacks is a sense of horror. Instead, the author presents a slow-burn psychological drama which her publicists have been able to market well - publishing rights have already been sold to countries such as the United States, Spain, Holland and Russia.

The narrator is the elderly Ginny, who lives alone in her dead parents' mansion, selling off the antique furniture for groceries, and accompanied only by the extensive collection of preserved moths left by her lepidopterist father.

Her mothballed life is shaken up when her younger, more vivacious sister, Vivien, decides to return to the family estate from London, where she has lived since she was a young woman.

Given that the sisters have not seen each other for decades, it is unsurprising when it turns out that there are some unresolved issues between them.

'I was always the sensible sister and Vivi the adventurer,' remarks Ginny. Like all her other remarks, this should be taken with a pinch of salt.

The soundness of Ginny's mental health is questionable from the start, when she mentions her obsession with time: 'I keep a number of clocks just so I can be sure that, even if one or two let me down, I'll always find the correct time.'

As the narrative flashes back and forth between the sisters' past and present, it is constant guesswork as you try to read between the lines to see what Ginny cannot, or does not, want to see.

The author, a film-maker who has worked on science documentaries for the BBC and the Discovery Channel, puts her prior experience with nature to good use in several stomach-turning descriptions of wildlife, such as this one about a pupating caterpillar, a vivid memory from Ginny's childhood (and a symbol of the hidden rot in her life):

'The caterpillar's shiny new underskin started to burst all over in tiny little uprisings, one at a time, a gash here, a gash there and then all over, and out of the holes popped the writhing, tapered heads of a totally different creature's larvae, tiny translucent maggots hungrily eating their way out of the caterpillar, devouring the body alive, from within.'

But a creepy atmosphere and goosebumps-inducing prose can get you only so far. An unreliable narrative becomes rewarding at the point where, despite the assertions of the narrator, the reader catches a glimpse of what the truth is, and shudders at the perversity of the narrator's delusions.

Unfortunately, this point does not come in this book. Incidents from the past - Vivien's fall from a tower in their childhood, their mother's fatal tumble down the cellar steps at a later date - are related in Ginny's typically muted manner. But the obvious implications - that both were pushed - seem not only hackneyed but also strangely irrelevant to the rest of the story, which concerns a dead baby which might or might not exist.

On the other hand, actually scintillating details end up as red herrings, never playing out into anything meaningful.

To Adams' credit, there were some wonderfully written, sinister moments which you thought might develop into something magnificent. Too bad it turned out to be a dull specimen after all.

If you like this, read: American Psycho by Bret Easton Ellis (1991, $25.03 with GST at Books Kinokuniya)

A young man is a wealthy investment banker by day and a rapist-murderer at night. Or so he says.

This article was first published in The Sunday Times on Aug 31, 2008.