Hiding in the glare of the spotlight Despite a glittering Hollywood career, the real Robert De Niro remains an enigma to most, says Allan Hunter

In an interview, every word is a prisoner, every sentence an agony. He only truly seems to find his voice as an actor,

an impression confirmed by

veteran director Elia Kazan who says: ''He finds release and fulfilment in becoming other people.''

What remains when he removes his make-up and abandons the world of make believe is known to only a few true intimates. Georgie Auld was asked to teach De Niro to play the tenor saxophone for his role in New York, New York (1977).

Nobody worked more diligently in the service of pretence. Auld admired his exhausting dedication but found De Niro the person to be ''about as much fun as the clap''. Thrilled to secure De Niro for a cameo in Brazil (1985), director Terry Gilliam recalls: ''We were all in awe

of De Niro, then we shifted round 180 degrees and wanted to kill him.''

All of these observations come from John Baxter's new biography of the reclusive actor. Baxter has a solid track-record which includes works on Steven Spielberg, Stanley Kubrick and Woody Allen.

It is still a little rash of his publisher to claim this as the first ''full portrait of the actor'', an assertion that Scotland's Andy Dougan, among others, would justifiably challenge.

Inevitably, it is unauthorised and those who have consented to talk to Baxter are on the

distant fringes of De Niro's

life. What we have is a

well-researched volume that

is strong on facts and detail,

but rather less valuable when

it comes to analysis or fresh insight. Baxter makes a persuasive case that De Niro's greatest gift to the cinema is rage. Anger has shaped his most famous and enduring performances in Taxi Driver (1976), the Oscar-winning Raging Bull (1980) and Cape Fear (1991).

Nobody on screen is more threatening or frightening when he makes a direct connection to the inner turmoil and outward violence of his characters. Through his lengthy collaboration with Martin Scorsese, De Niro is most closely associated with men of violence who operate on the wrong side of the law. You expect his own story to be one of a troubled childhood, delinquency, a raw talent honed on the streets that he would one day return to own. The reality is very different, and both De Niro's life and the biography are full of surprises.

De Niro was born in New York, but it was a bohemian New York of artists and writers. Born in 1943, he grew up in a loft apartment in Greenwich Village. Both his parents were painters. His father worked

as a waiter with Tennessee Williams and was predominantly gay. His mother, Virginia, was a contemporary of Jackson Pollock and knew Peggy Guggenheim.

When his parents divorced, it was without rancour. His mother exhibited at the Biennale in 1947, wrote pulp-fiction detective stories and reinvented herself as a successful businesswoman. Robert senior remained a struggling painter all his life. It was a very cultured and liberal upbringing in which the young De Niro made his schoolboy acting debut as the Cowardly Lion in The Wizard Of Oz.

Baxter claims De Niro's father as one of the most important influences on his career and his character. His father is recalled as a man with a ''face as sharp as a switchblade and a temperament to match''. Father and son would go to the movies together, bonding over double-bills of old Greta Garbo movies. The desire for fame and achievement was the means by which a shy De Niro chose to prove himself to a man who was never held to be affectionate or gregarious.

Baxter is quite acute at tracing De Niro's acting lineage.

A less perceptive biographer would make the obvious connections to the soul-searching realism of the method actor generation, claiming De Niro as the obvious descendant of Marlon Brando, James Dean and Montgomery Clift. Baxter suggests that De Niro is more rightly related to an earlier generation of movie actors, such as Lon Chaney and Paul Muni, who relied on physical transformation as the means of reaching the truth of the characters they were playing.

De Niro's acting is based on detailed, obsessive research in which he eventually earns the right to play a character. His performances are built from the outside in rather than from a need to reveal aspects of himself. The last thing he wants to see on the screen is Robert De Niro. Baxter believes he found anonymity in ''the least likely of all places - the spotlight''.

Fans of De Niro will savour the detailed accounts of his lengthy association with director Martin Scorsese and the making of such landmark films as Mean Streets (1973) and Raging Bull (1980).

The author's research pays dividends in the details of the carousel of casting possibilities which saw De Niro, Al Pacino and James Caan in constant competition for the same roles in the 1970s. De Niro lost both The Gambler and Funny Lady to Caan.

Baxter is much more circumspect when it comes to De Niro's private life. He provides details of marriages, children, messy liaisons with the likes of Naomi Campbell and allegations of drug-taking, but leaves you feeling that there is a good deal more that remains unsaid. Perhaps it is only fitting that the emphasis is on the career, when that seems to be the arena in which De Niro is fully alive and able to express himself.

The one fact that every De Niro fan and any biographer must face is that De Niro has increasingly sacrificed quality for quantity in his career. He has made almost 30 films in the past decade, a period that Baxter easily compresses into the last 60 or so pages of the book.

His biggest commercial successes have come parodying himself in comedy hits such as Analyze This (1999) and Meet The Parents (2000). Sequels to both films will be released in 2003 when De Niro reaches 60. It seems a long way from the days of Taxi Driver, The Deerhunter and Raging Bull, when every De Niro film was an event. There is a feeling that he has tarnished his reputation by squandering his talent on inferior but lucrative projects.

His energies seem to have been more fully engaged by his new roles as property developer, restaurateur, movie mogul and global ambassador for New York. Nobody worked harder to restore the city's morale after the events of September 11.

Baxter bravely concludes: ''Raging Bull was the apotheosis of De Niro's career as an actor,'' and almost suggests that his recent career can be viewed in terms of a significant decline and fall. Whether that says more about De Niro or the state of modern Hollywood film-making is a moot point that Baxter never addresses. He cannot explain why the performances of the Ageing Bull

lack the intensity and visceral impact of the past.

Nor can he quite unravel all the factors which forged that intensity in the first place. His biography may be informative and highly readable but it is not definitive and even under relentless scrutiny the sphinx manages to retain most of his secrets.

De Niro - A Biography, by John Baxter is published by HarperCollins, priced (pounds) 18.99.