H Hamilton £17.99 pp444

“His sexual history was his own,” Paul Theroux says of Slade Steadman, the hero of his 26th work of fiction. “This revelation . . . was a true epiphany.” The claim dubiously identifies the erotic with the authentic, but truth in fiction is established by the reader’s experience, not by the writer’s assertion.

Steadman is a middle-aged writer who long ago enjoyed a one-book success. Publicists have transformed his account of travelling the world as a “trespasser” into a lucrative marketing opportunity, while he himself has become separated from his work. On a trip through remote parts of Ecuador with his sort-of former lover, a doctor called Ava, he uses a drug that makes him temporarily blind and grants him astonishing insight into reality. Back home in Martha ’s Vineyard, he begins to write an outspoken novel of sexual adventure, with Ava’s renewed physical and occasional psychological support. He becomes a celeb, as much for canny exploitation of his apparent disability as for his literary achievement. Then nemesis arrives in the form of true blindness.

The theme has been emphatically anticipated throughout the book. There has been a blind robber, a blind priest and a blind whore muttering “I am you.” Steadman and Ava have worn masks while having sex and had their eyes bound while travelling to the drug’s secret source, the mind-altering datura. There have been portentous allusions to Tiresias and Borges. Steadman’s transient blindness is the source of his vision. He is aware of every sensory nuance and every moral obliquity. He is even credited with sensing “the corruption and the untruth” at Bill Clinton’s White House — for this you need rare drugs?

Neither travel nor domesticity broadens Steadman’s mind. He loathes his modish readers. There is a sharp portrayal of some American eco-tourists who treat other countries as a stage for their egotism and whose dismissive chatter (“Bali is a toilet”) sounds miserably plausible. But the misanthropy spreads, no longer restricted to those who create a “captive and violated world”. Steadman can perceive people’s shabby furtive secrets (including Clinton’s) but never their concealed charity or hidden nobility. He thinks of “himself as the feline prophet of a new religion”, but his aperçus don’t amount to much more than a metaphysical party trick.

Although the book centres on what Steadman calls “the god-like realm of the erotic”, nothing — however explicit or transgressive — seems to validate his (or is it Theroux’s?) claim that “the truth was sexual”. In fiction and in life he re-enters the world of teenage desire, recalling blindfold orgasms with a friend’s mother and the fetishistic games they played with “the straps and softness of her lingerie”. The writing rarely gets beyond soft porn, although it goes on for pages. Women all over America are prepared to offer themselves to him on slight acquaintance, but it’s hard to believe in them.

We learn little about his former wife, except that she was ignorant and sulky, and used to beg for sex “like . . . a coke whore”, but — unforgivably — didn’t finish reading his book. Ava, by contrast, is the “ideal woman”. She not only reads Steadman’s book, she helps write it. A respected doctor who is erotically aroused by performing surgery, she is ready to dress up as a prom queen or bring girls home for threesomes. Long-legged, athletic and full-lipped, she is a devoted virtuoso of oral sex, happy to perform in the library. This may well have special appeal for middle-aged writers, but after such unfailing compliance her sudden independent anger is hard to credit.

Some enchanting descriptive moments evoke the rainforest and the city. New York is directly there on the page, caught in ten words: “The flat-faced buildings, the surly windows, the fleeing pedestrians.” However, there is too much obtrusive commentary, glib irony and diffuse repetition. The Faustian nature of Steadman’s bargain is flagged by awkward references to “Mephisto walking shoes” and allusions to Marlowe, while Theroux’s own phrase for the result of moral trespass (“lost in the seamless darkness of his despair”) is mere cliché. Although written with his familiar fluency, and with occasional flashes of considerable power, Blinding Light is overlong, self-indulgent and finally unconvincing.Any possibility of “a true epiphany” is lost long before the novel ends.

Available at the Books First price of £14.39 plus £2.25 p&p on 0870 165 8585

Explore Books

• Books Group

• Book Extracts

• Book Reviews

• Audio Books

Times Recommends

• Sarah Palin and the Palindromes: 7 extraordinary connections
• Physics for Future Presidents: The Podcasts
• 10 Books Not To Read Before You Die