Faber remains something of an enigma. Born in the Netherlands in 1960 but resident in the Scottish highlands, he is a hard writer to place - and not just in geographic terms. His instincts are both populist and experimental, historical and contemporaneous - and will only enhance his status as a novelist who combines addictive, readable narratives, big ideas and a quirky way with fictional genre.

In certain respects, the narrative recycles tropes present in : extra-terrestrial imperialism, a jaded portrait of corporate interests, nature on the verge of a breakdown, and erotic action in cars.

In , this occurs immediately as our central protagonist, Peter Leigh, bids a rather clumsy sexual to his wife, Bea, in a lay-by near Heathrow. The sex is short, brutal and unsatisfying, but has long-term consequences for both participants. As the couple complete a largely wordless but fraught journey to Heathrow, Faber hints that they are facing a crisis at once exciting, unavoidable and terrifying: "[Peter] knew there was quite a decent chance he would die in the next thirty days, or that, even if he survived the journey, he would never return."

The truth is delivered in delicious slices: Peter, we learn, has been hired by the sort of faceless corporation that darkens science fiction dystopias. His mission is to spread the word of god in an unstable region. The destination, which Faber reveals like a magician whisking a tablecloth from under a fully laid dinner setting, is another planet, christened Oasis. There's a nice joke in which Peter is told he is a "people person" who will "go far".

Oasis has been colonised by Peter's firm, USIC, which wants him to establish amiable relations with the locals who control the means of food production. They are a strange bunch, speaking English whose odd accents Faber transcribes with hieroglyphics and have faces that remind Peter of foetuses curled side by side. Some are already devout, and share the name Jesus Lover.

Peter's evangelism has more than a hint of about it, as if Faber takes seriously Marlow's sardonic use of "Pilgrims" at the start of Joseph Conrad's novel. Images of illumination and obscurity run throughout the novel, often expressing Peter's mission to bring Christianity to unbelievers. "The world looks nicer with man-made lights," he argues a little allegorically before explaining "unspoiled nature is supposed to be the ultimate in perfection", but, he says, electric lights "make a night drive like this bearable. Beautiful even. I mean, just imagine if we had to do this drive in total darkness."

Peter falls head over heels for the Oasans, going native in dress and behaviour. Just in case we miss the Conrad allusion, there is even a mythic predecessor called Kurtzberg whose success with the indigenous population obsesses his successor.

What drives the novel is the impact Peter's relationship with the Oasans has on that with Bea back on earth. This is narrated in hi-tech epistolary form: love letters, essentially, that are distorted by the context of each writer's life. On Oasis, Peter begins by exhibiting selfless, energetic empathy with the "freaks" as they are called by USIC employees. Yet, having been greeted like the second coming, he starts to behave like one - donning robes and sandals, neglecting his personal grooming, refusing food, and wandering any wilderness on hand.

Quite what sacred good he is doing seems unclear. The Oasans need little converting and are, if anything, even more fanatical for Jesus than Peter.

The suspicion grows that the simple, undemanding ease of the Oasans' company is firing his missionary zeal, which Faber weighs against the unceasing demands of Peter's ministry on earth. "He was looking forward to living with the Oasans again. It truly was a privilege. Ministering to his congregation in England was a privilege too, but it was also difficult sometimes, what with the perverse, immature behaviour that various individuals were liable to spring on you."

Humans were "precious souls", he notes a little sententiously, but "the Oasans were a tonic for the spirit". Bea is not slow to notice that Peter's mission tends as much to his own spirit as anyone else's. His growing moral myopia is elegantly exposed by his letters, which become more curt, elliptical and pompous as he does.

Initially, Peter is simply concerned about his ability to convey the strange reality of Oasis to his wife. Faber, who is acutely alive to the line dividing the literal from the metaphorical, portrays Peter as being unable to conceive of the Oasans in anything other than earthbound images. While his fervour to learn their hieroglyphics initially reinforces his confusion, it eventually expresses Peter's own alienation from his past: his final speech, delivered entirely in Oasan, needs some serious decoding. And if one has been paying attention, one will be able to transcribe it.

Peter's limitations as a correspondent are not just a question of prose style, but a dearth of sympathy and imagination as a reader. This is laid bare by his woeful misinterpretations of Bea's increasingly terrified messages which describe a country and planet in collapse. Nature has turned terrorist, wiping out the Maldives, parts of Guatemala and Korea. England is decimated by food shortages, looting and economic breakdown. Her valiant attempts to downplay the crisis on his behalf fall on deaf ears - or at least ones finely attuned to Oasis.

Bea caves in when Peter's myopia, bordering on narcissism, get the better of her. In response to his fatuous idea of selling up and moving to a rural area, she snaps: "The housing market has COLLAPSED. Like just about everything else in this country IT IS KAPUT. Couldn't you guess that? … All those nice young couples all over the UK are frozen with TERROR."

Peter, understandably, struggles to absorb the sheer scale of her crisis, whether spiritual or real. Bea's words, which are never less than compassionate and kindly, sound unreal from the distance of Oasis. What is less forgivable is his passivity in the face of his wife's distress, her loneliness and growing nihilism. Her final, devastating words on the subject: "There is no god."

Peter's Christian consideration, which on Oasis expresses itself in muscular activity (working the fields, building a church), sounds abstract and almost cruel in his letters to Bea. One wonders whether his faith, which he found after years of alcoholism, drug addiction and homelessness, is more personal therapy than social conscience.

It is too tempting to read the novel as an unbridled exposé of Christian hypocrisy. Faber asks uncomfortable but open-minded questions about suffering and altruism, co-operation and exploitation, duty and desire, the demands of the community and those of the individual. Movingly and convincingly, this is expressed through a sophisticated, grown-up love story about two people who lie, cheat and fail one another, but strive to find ways to love one another, even if this means sacrificing their deepest desires for someone else.

The final pages are moving. Peter's devotion to the Bible (that "Book of Strange New Things" as the Oasans call it), finally moves from the abstract to the real: "He thought of Matthew's last words, and the meaning they could have for two people who loved each other: I am with you always, even unto the end of the world. Amen."

Faber is a fantastically gifted writer, an addictive storyteller with a nuanced command of language. was worth the wait.