The Flame Alphabet, By Ben Marcus

In its eerie fantasy, this mysterious novel explores the secrets of language, faith and family

If there is such a thing as experimental writing, then American writer Ben Marcus sits firmly in its vanguard. His first book, The Age of Wire and String (1995), is almost totemic in its weirdness, a bewildering pocket encyclopedia that pursues its nonsense so intently that you begin not so much to believe everything you read in it, as to lose faith in the meanings you've mindlessly drawn from everything else you've read.

The Flame Alphabet is Marcus's most substantial book since then, and the closest to what might be called a proper novel. Its premise is simple and arresting. It is set in an America under attack, from within, as its adults fall prey to a contagion carried on the speech of children. The story centres on a family in New York State who become exposed to this "language toxicity". At first the parents, Sam and Claire, refuse to believe their decline is caused by their 14-year-old daughter, Esther, telling themselves their skin complaints, incontinence and lethargy are just signs of ageing. Sam experiments with home-brewed medicines and protective paraphernalia, allowing Marcus to deploy the kinds of arcane technical terminology that made Wire and String such a joy: "On top of these I crammed a raw stash of anti-comprehension pills, a child's radio retrofitted as a toxicity screen, an unopened bit of gear called a Dräger Aerotest breathing kit, and my symptom charts."

The question of the hidden power of language is given a further twist by the fact that Samuel and Claire are members of a Jewish sect, the Forest Jews, who worship in secret, listening to sermons in a hut in the woods via a strange apparatus that seems to have strayed in out of a David Cronenberg movie.

The passages that explore the place of the written and spoken word in Judaism are fascinating, and become more so when a repellent and charismatic man called Murphy turns up and starts pulling all Samuel's carefully argued strategies out from under him.

The book does wobble once the plot kicks in, with the grown-ups being evacuated, and Samuel fetching up in a laboratory, researching new alphabets that might make human communication safe again.

In the end, The Flame Alphabet does regain its power to disturb, by revealing itself as a parable not just of language, or religion, but of parenthood. For Esther is not the perfect child, but a surly, vindictive presence, as eager as any teenager to turn her words into a weapon. There is a chilling image of her kneeling over her sick mother, "opening her throat for the pure injury to pour out".

Marcus has written a gnarly, difficult book, part-fairy tale, part-horror story, part-literary dissection of these: a mutant worthy of the best experimenters.

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