BOOK REVIEW / A highly tantalising layer-cake: Natasha Walter on Philip Roth's ambitious new novel full of Mossad manoeuvres, mistaken identities and missed chances: Operation Shylock - Philip Roth: Jonathan Cape, pounds 14.99

ISRAEL is the perfect place to set a novel of mistaken identity. It is the country where everybody seems to be speaking in tongues, rehearsing learnt justifications and old hatreds, and continually refining the barriers to straightforward communication. The first chapters of Philip Roth's new novel, Operation Shylock, convey this atmosphere as no other literary work has ever done. Forget the sights, forget the smells, forget the domes and the landscapes, this is Israel stripped down to her defining voices.

One of the novel's best set-pieces has the narrator, Philip Roth, sitting in the courtroom of the Ivan Demjanjuk trial. He cannot hear what is going on because his translating headphones don't work, but he can tune into one after another of the contradictory streams of consciousness, including that of Demjanjuk himself in the guise of Ivan the Terrrible: 'What a job] A sensational blowout every day] One continuous party] Blood] Vodka] Women] Death] Power]'

The novel's basic premise is that a man pretending to be Philip Roth is travelling the world proclaiming a new doctrine to save the Jews. The doctrine, Diasporism, is a movement to lead them out of Israel and back to the places of their erstwhile destruction - Germany, Poland, Lithuania, Czechoslovakia. The real Philip Roth's first encounter with his double in Jerusalem is tricked out with a gently understated uncanniness; the double is missing the same button from his jacket, has the same pocketbook, knows details of Roth's past that even Roth has forgotten. This doubling device, and the simultaneous plausibility and craziness of Diasporism, feed well into the mazy tragedy of the real Israel.

Thus, passing through a market soon after this meeting, Roth meets an old university friend, George Ziad, a Palestinian who has been dragged back to his homeland by the struggle. His speech has been colonised by his anguish, he talks in three-page blurts of wired-up, justified rancour. In response to the tragedy before him, Roth himself suddenly dons the mantle of his double, and preaches Diasporism to Ziad. Unsurprisingly, the Palestinian loves it: 'Old friend, we need you, we all need you, the occupiers as much as the occupied need your Diaspora boldness and your Diaspora brains.' Subsequently Roth preaches it again to a mixed-up Israeli soldier who hates what he is doing in the Occupied Territories but is forced into staying because of his sense of family loyalty: 'My father survived Auschwitz when he was 10 years old. I am humiliated that I can't survive this.' With this kind of precise mimicry, and an eye for the freakishly Kafkaesque, Roth plunges into the state where right and wrong shiver and melt at every step forward.

But the promise of this glittering opening is not sustained. In his most ambitious work ever, Roth has bitten off a great deal more than he can cope with, and gristly lumps of pure tedium litter the rest of the novel. Despite the rather silly claims for the book's status as non-fiction that Roth has made in the afterword and in interviews, after this clever beginning there is hardly a moment that can lay claim to verisimilitude.

The treatment of sex, previously one of Roth's liveliest cards, is a small case in point. The impostor's girlfriend is meant to be a femme fatale, but her charms are noted in such a generalised jumble: 'a voluptuously healthy-looking creaturely woman . . . a tantalising layer cake of female excitement' that they fail to convince. Roth finally makes love to her, but since it is just a moment of plot propulsion, with so little particularity or immediacy, we feel sure that it hasn't happened anywhere, not even in Roth's own imagination.

After a while, one begins to suspect that Roth could not make anything happen in this book if he tried. His most recent works, Deception and Patrimony, also suffered from a notebook approach, but hardly came close to the windbaggery of this unedited, grumbly series of arguments and counter-arguments. When he remembers the plot, Roth lays a few implausible red herrings - a suggestion that the impostor may try to kidnap Demjanjuk's son; and a long scene in which Roth is taken off to a building by strangers and believes that he has been abducted, for instance. But one gets twitchy just waiting for these to fizzle out - at the end of his abduction, Roth has to be shown the door about five times before he will leave, first demanding a taxi, then a limousine, and finally returning for a book that he has forgotten.

The final conceit, that his 'abductor' is in fact a Mossad agent, and that Roth takes on an assignment for him but is forced to destroy the description of that assignment, which originally made up the last chapter of this 'novel', because it reveals too many details about Mossad manoeuvres, plays to an empty house. Out of duty, the reader plods through it, picking up and discarding all the reflective baubles: the Hebrew verse on the wall of the room where Roth takes his momentous decision is that in which Jacob wrestles with the angel; even the final 'confession' of the novel's truth ends with the U-turn: 'this confession is false'.

If there is any deeper meaning to the endlessly circular logic that marks these last sections, it is certainly not that terrible loss of morality generated by the Israeli-Palestinian struggle, which is so movingly gestured at towards the beginning of the book, but, rather, Roth's continuing obsession with his own ego.

In the novel's own scheme of things, the impostor is important not because of his Freudian uncanniness or because of his dangerous Diasporist doctrine, but more because he shows what a wildly difficult, dangerous thing it is being Philip Roth, what with fans who stake out your dad's house and hijack your own past. Some of this is executed with teasing detachment, but from the big problem of this obsessed double to small embarrassments like the hotel concierge who jokes 'This is no longer the lobby of the King David Hotel, it's the rabbinical court of Rabbi Roth. All his fans won't leave him alone. Every morning, they are lining up . . .', Roth can't stop selling us the size of his reputation.

The best metaphor of all for this novel is a scene where the impostor gratuitously shows Roth his penis, and we are subsequently told by the impostor's girlfriend that its imposing size and length are only due to a penile implant. Although this may be a latent boast of all that the double is trying to live up to, it returns to haunt us. This novel, likewise, may be a large and showy thing at first glance, but turns out to have no lifeblood, no satisfying pulse.

(Photograph omitted)