Vanessa Redgrave: A grande dame who won't conform

An unprecedented tribute from the Academy of Motion Pictures in mid-November and, earlier this week, a Best Supporting Actress gong at the British Independent Film Awards for her overpowering performance as Volumnia, the iron-willed matriarch in Ralph Fiennes's film version of Coriolanus. Not to mention all those reviews raving about her deeply funny and touching portrayal of a cantankerous, blinkered Southern matron in the current West End hit, Driving Miss Daisy. It's been a season of luxuriant bouquets for Vanessa Redgrave. But there have been brickbats, too, and you cannot get to the essence of her art unless you also take these into account.

On the one hand, the Oscars travelled to London for the first time ever to mount an evening in honour of her 50 years in film. It was hosted by David Hare, who praised her "ability to make thinking look fun, to lend glamour to thought as much as to feeling. In her performances there is an interior quality which has been much remarked... the sense that the emotion or conviction is drawn up from a deep, almost inaccessible place. But less remarked is the shine she then puts on it. It is as if she both draws light and reflects it."

On the the other hand , she was mocked in a broadsheet showbiz column as a self-involved, interfering "celebrity angel of death" whose visit to meet and defend the Dale Farm Travellers would virtually guarantee their eviction from the Essex site.

That phrase was unfortunate, given how well-acquainted with angels of death the Redgrave acting dynasty has become in the past few years. Natasha Richardson, the older of her two actress daughters by director Tony Richardson, was cut off in her prime in March 2009, after a skiing accident – followed a year later by Vanessa's brother Corin and her sister Lynn.

It's typical of the actress's idealism and guts, though, that, just seven months after the untimely loss of Natasha, she fulfilled a commitment to reprise her role in The Year of Magical Thinking, a solo show based on Joan Didion's intimate memoir of her struggle to come to terms with the death of her husband and the fatal illness of her daughter. Hair scraped back in a pony-tail from the long, gaunt face that is matchless in its emotional transparency, Redgrave had triumphed in the part on Broadway and in London. But now the subject matter was horribly close to home.

Putting duty before personal feelings, she pressed ahead. Staged in New York's Cathedral Church of St John the Divine, it was a benefit performance for causes important to her – Unicef (for whom she is a Goodwill Ambassador) and UNRWA, the agency that helps Palestinian refugee families. At the Oscars tribute evening, her friend Eileen Atkins said that "courage" and "radiance" were the two words most used about Redgrave. "And I think," she went on, "that comes from her true belief that basically mankind is good. She believes in humanity, and not many people do."

This remark pierces to the heart of the actress's greatness and also implicitly explains why her genius will always remain controversial. People like the safety of cynicism and Redgrave is as lacking in cynicism as she is weirdly immune from the compulsive English habit of irony, that approved way of asserting one thing while meaning the opposite. You wouldn't, therefore, necessarily want to cast her in, say, Restoration comedy. By contrast, in his review of her brilliant performance as Lady Torrance in the Peter Hall production of Orpheus Descending, the critic Frank Rich rightly observed that Vanessa Redgrave and Tennessee Williams are made for one another because they both "run at life bravely, openly, without defences and without fear of their inevitable destruction, like great, beautiful deer bounding across a highway after dark".

Her movie career took off with her iconic portrayal of an enigmatic Sixties swinger in Antonioni's Blow-Up (1966). More than 100 films, six Oscar nominations and one win (for Best Supporting Actress in Julia) later, we can now rejoice in the wealth of her superlative recent work. It's hard to conceive of more powerful acting in merciless close-up than that which Redgrave produces in the coda to Atonement, where she plays the elderly, dying Briony under polite interrogation from a TV interviewer. The impassioned, haggard gaze and the uneasy rasp of her voice take you – with characteristically devastating immediacy – deep into the soul of this writer and her desperate need to believe that, by concocting a fictional happy ending in a novel, she can make amends to the now dead couple whose lives she ruined by a less beneficent lie.

Redgrave was catapulted to glory as a stage actress by her gamin, free-spirited Rosalind in a 1961 production of As You Like It at Stratford. The critics went into rhapsodies, with Bernard Levin gushing that, "This Rosalind is a creature of fire and light...her body a slender supple reed rippling in the breeze of her love, etc etc." Since then she has excelled in a wide repertoire ranging from Ibsen to Coward, Chekhov to O'Neill. Her interpretations are often startlingly original. When she received her BAFTA Fellowship in 2010 at the Royal Opera House, Redgrave gave a clue as to why. She revealed that she had learned a great lesson from Maria Callas who said you should put the truth of your thoughts and feelings first; the sound of your voice would come after.

Redgrave's work extends that proposition, suggesting that, provided an actor has command of the emotional roots of a part, he or she is free to wave the leaves and branches in many different directions. Hence the thrill of unpredictability in her performances that continue to take fresh risks in matters of rhythm, intonation, emphasis and gesture throughout a play's run. The results sometimes feel sublimely revealing and wilfully eccentric within the space of one line. Her portrayal of Ella Rentheim, for example, in Richard Eyre's NT production of Ibsen's John Gabriel Borkman may have been marred with irritating mannerisms, but she moved you to the core with her unique brand of emotional honesty.

Redgrave's political activism has sometimes been questionable, especially during her days as a leading member of the Trotskyist Workers Revolutionary Party, and it has sometimes been costly. When she characterised the protesters burning her effigy outside as "Zionist hoodlums" during her Oscar acceptance speech, it led to her effective blacklisting. But you can't deny that the activisim is intimately connected to the lit-from-within quality of her acting and its impetuous ardour. And even now, Redgrave could never be categorised as "national treasure". She is, to her credit, too angular and unbiddable.

And she cannot be understood except in relation to her family. The tabloids, of course, slapped the stupid "Curse of the Redgraves" label on the recent spate of tragedies that have befallen the clan, the implication being that any brood spawned by a Leftie and practising bisexual, as the great actor Sir Michael Redgrave was, deserves all that is thrown at it. Corin, her fellow activist, wrote a wonderfully empathetic memoir of their father, in which he explored the cost to Michael, his wife, Rachel Kempson, and their family of the double life he was forced to lead because of his outlawed sexuality.

Both Corin and Lynn have composed plays about a clan that can trace the acting gene back to Michael's father, Roy Redgrave (1873-1922), a feckless barnstormer who decamped to Australia and the silent film industry. Its members have often had differences over politics and parental priorities. But in order to act together, they have been prepared to put these aside – as they did gloriously in the 1990 Three Sisters in the West End where Vanessa and Lynn were joined by Corin's daughter, Jemma, and in the NT Cherry Orchard a decade later in which Vanessa and Corin brought their shared past to bear on those self-indulgent siblings, stalled in nostalgia, Ranevskaya and Gaev.

It's not through nepotism but through inherited gifts and a sense of natural succession that Natasha and Joely have so often played the daughter or younger self of the characters portrayed in films by Vanessa (Joely is doing this at the moment as Elizabeth I to her mother's wily old monarch in Anonymous). And next year, at the Rose Theatre in Kingston, Joely will follow in the footsteps of Vanessa and her late sister who both won resounding acclaim as Ellida, the heroine who is stranded out of her element in Ibsen's The Lady From The Sea. Why? From the pressures of pedigree or because of an inspiring family tradition? Most probably the latter, given the beacon-like example of her mother's fearlessness. Laurence Olivier announced Vanessa's arrival in the world from the stage of the Old Vic where he was playing Hamlet with a cast that included her father: "Ladies and gentlemen, tonight a great actress has been born. Laertes has a daughter." The Best Actress nominations are starting to come in for Driving Miss Daisy and she is being tipped for an Oscar for Volumnia in Coriolanus. Seventy-four years later and with no sign of slowing down, Vanessa Redgrave is still peerlessly proving the truth of Olivier's prophecy.

A family affair: The redgrave acting dynasty

SIR MICHAEL REDGRAVE (1908-1985)

Handsome, complex classical actor who was equally brilliant in films. He played Vanya to Olivier's Astrov in the legendary 1962 production at Chichester and gives a quietly devastating performance as Crocker-Harris, the desiccated classics master, in the screen version of Rattigan's 'The Browning Version'.

RACHEL KEMPSON (1910-2003)

She famously jumped into the stalls of the Royal Court to box the ears of two hecklers during John Osborne's 'A Sense of Detachment' (1972). But as matriarch to a gifted, difficult dynasty, her role was that of peace keeper. Played Regan to her husband's Lear in 1953 and was a luminous Lady Manners in 'The Jewel in the Crown'.

VANESSA REDGRAVE (1937- )

Tennessee Williams declared her "the greatest actress of our time in the English-speaking world" and, early in her career, Noel Coward told her, admiringly, that she was incapable of being untruthful on stage. Her passion for theatre, film and radical causes remains gloriously undimmed.

CORIN REDGRAVE (1939-2010)

Incisively intelligent actor who excelled at portraying compromised Establishment figures (Sir Roger Casement, Sir Anthony Blunt et al). Virtually blacklisted for his WRP political activities in the Seventies, he came into his own in the late Eighties with the advent of perestroika and after the death of his father.

LYNN REDGRAVE (1943-2010)

Twice Oscar-nominated and a warmly witty and sympathetic talent, Lynn used to joke that, "It was always 'Corin's the brain, Vanessa's the shining star, oh, and then there's Lynn.'" She wrote and performed in 'Shakespeare For My Father', a rueful, funny-sad one-woman show of reflections from the least favoured child of the remote Sir Michael.

NATASHA RICHARDSON (1963- 2009)

Haunted by the family name, she decamped to New York in the early 1990s and won acclaim as O'Neill's Anna Christie and as Sally Bowles in Sam Mendes' 'Cabaret'. She was beginning, in the 2003 revival of 'The Lady from the Sea', to equal her mother on her own turf. A huge loss.

JOELY RICHARDSON (1965- )

Whether bouncing up and down on Sean Bean as Lady Chatterley or squaring up to Glenn Close in '101 Dalmatians', she is a lustrous presence. First played the younger self of a Vanessa character in David Hare's 1985 film 'Wetherby'. Now the Rose Theatre of Kingston has a coup as she takes on the family challenge of 'Lady from the Sea'.

JEMMA REDGRAVE (1965- )

An immensely touching Irina to her aunts' Olga and Masha in the West End 'Three Sisters' (1990), she had established herself as a stage actress of great finesse, before concentrating on TV work. Made a welcome return in the US tour of the Tricycle's 'The Great Game: Afghanistan', which included performances for the Pentagon.