A very British invasion: UK hails its 21 Oscar nominees

Best Actor: Daniel Day-Lewis 'There Will Be Blood'

It's a mark of a great screen performance that everyone wants to get in on the act. Daniel Day-Lewis's Oscar-nominated lead in There Will Be Blood is rapidly becoming the most-imitated Hollywood turn since Jack Nicholson's "Heeeere's Johnny!" or even De Niro's "You talkin' to me?". Everyone has their own favourite riff to mimic from Day-Lewis's monstrous oilman Daniel Plainview: for some, it's that strange shuffle from the final scene; for others, the furiously bellowed "I drink your milkshake! I drink it up!" – a line that's been honoured with its own website.

That the performance has been seized upon as a buffs' in-joke is just testament to the respect it has generally inspired, and if Day-Lewis wins the Best Actor award tonight, few will demur. Few, but certainly some: there are numerous internet forums dedicated to the "genius-or-ham?" debate.

For my money, Day-Lewis's performance fits both the role and the film, which is conceived less like a realistic drama than some dark modernist opera. It's the second time that Day-Lewis has acted in such an extravagant register: he was even more barnstorming in Gangs of New York.

Day-Lewis's Daniel Plainview restores the grand register of nerves and sinew to the usually low-key craft of realistic screen acting. His characterisation belongs to an older thespian tradition: while drawing on the unmistakable boom of the late actor-director John Huston, it also echoes such veteran "sacred monsters" as John Barrymore and Charles Laughton.

While he's never been a truly commercial name, Day-Lewis has raised his stock by making appearances a rarity, with only three films this decade and five in the 1990s. They haven't always made a mark. His last film, 2005's The Ballad of Jack and Rose, a family melodrama written and directed by his wife Rebecca Miller, barely troubled the box office. Other films have passed under the radar, including Nicholas Hytner's The Crucible.

But when Day-Lewis scores, you sit up and take notice. His earlier performances in Jim Sheridan films – as Christy Brown in My Left Foot and Gerry Conlon in In the Name of the Father – established his ability to disappear into a part, body and soul. And while it's those self-transformations that made his name, his urbane lead in Martin Scorsese's The Age of Innocence showed the finesse achieved when he turns the volume way down.

Day-Lewis is legendary for his intense methods: he spent two days in a cell without food or water to play Gerry Conlon and learnt to hunt and skin animals for The Last of the Mohicans. But he's reluctant to discuss his methods. The one time I interviewed him, in Dublin in 1993, he told me that whatever exercises he undertook were "tools, ways of understanding, which you hope will free your imagination into a kind of spontaneity when the moment comes". If those tools worked, he said, you might even not remember making a particular film: "When the film starts to roll ... you aspire to be unconscious."

For all the talk of eccentricity, Day-Lewis didn't strike me as odd: just cheerfully, thoughtfully confident and a touch dandyish, turning up in biker leathers and guffawing about an affable beef he was having with director Stephen Frears (who launched him in 1985's My Beautiful Laundrette). And he ate only fruit salad for lunch. Stranger habits have been known among actors.

In terms of physical preparation for There Will Be Blood, Day-Lewis has said: "There wasn't anything to do but stay fit and start digging holes." The digging paid off: the film begins with him down a pit. You believe in him absolutely as a prospector, not as an actor playing tough. That's the difference that Day-Lewis brings: you couldn't imagine Tom Cruise wielding a pickaxe. Nor can you imagine that, like De Niro or Nicholson, we'll see Day-Lewis in comedies about cranky OAPs. Daniel Day-Lewis is in a very peculiar league of his own, and we may be drinking a celebratory milkshake for him tonight.

Best Actress: Julie Christie 'Away from Her'

If Julie Christie wins the Best Actress Oscar tonight, headline writers across the land will rejoice. But there are those who will feel that the award is unmerited. One article in the past few days drew attention to the opinions expressed on her film, Away from Her, by the critics who sit in judgement on all things arty for Newsnight Review. "Inaccurate, sentimental American rubbish," they crowed. The same article questioned the wisdom of interviewing "sacred cow" Julie on Radio 4's Today programme "as if she's a cross between Mother Theresa and Grace Kelly". Elsewhere, the praise for her was tempered with resignation that she would want to advertise her politics in any acceptance speech.

But then she does – unwittingly – attract a degree of ridicule. On Radio 4 last week she remarked that the two greatest disappointments in her life were contracting sinusitis at 14, which stopped her entering her pony club gymkhana, and the time the Sandinistas lost the election in Nicaragua. Actors with political views are considered fair game by those media that go against the mainstream. Actors, from Charlie Chaplin and Paul Robeson to Jane Fonda and Richard Gere, have been attacked and reviled in print by the media of the Right. On occasion, it has wrecked careers of major talents. Christie, one feels, is too used to the opprobrium to care.

Her political views are the result of a deep personal sense of injustice and compassion. She refers to herself as "an ideologue" by which we can infer she is somewhat left of centre without necessarily cosying up to a political party.

Christie holds a unique place in British life. She is the star who captivated men's hearts through her sexual charisma and beauty. Yet from the beginning, she resisted the accolade of sex symbol with a ferocity that has mellowed over the decades. "I was too pouty to be beautiful," she said recently. Maybe so, but the face that graced Billy Liar, Darling, Doctor Zhivago and The Go-Between was genuinely iconic. Now that the looks have matured into a more or less natural image of a handsome older woman, it is not hard to understand why Christie should still exert a grip on our imaginations.

She has lost none of her conviction, though now it is leavened with a good deal of self-deprecating humour; she is a fundraiser for groups such as the Medical Foundation for the Victims of Torture and Survival International. And she is, if anything, a better actress now than she was in the 1960s. Indeed, many of the smaller roles she has taken since her heyday have proved remarkable – from her grief-stricken madness in Fools of Fortune to the autumnal romance of Afterglow.

My first encounter with her was a shock. My image of the youthful Christie had a severe reality check when she appeared in a baggy sweater, with messy hair and no make-up. She looked as if she'd come straight off the farm which, in essence, she had. My second encounter was in her dressing room in a West End theatre during a revival of Harold Pinter's Old Times. Her hair was impeccable; she wore fashionable clothes and her face was radiantly enhanced with make-up.

It was here that she put the rumours of a facelift to rest. "No, I haven't had a facelift," she said. "I had what's known as a neck-tuck. It just saves having to be pinned back with sticky tape for photographs." She told me that she had had memory therapy for learning the lines which had worked well enough to assuage her stage fright.

Today, her candour, her humour and a wobbly sense of self-esteem are intact. It is 43 years since she won an Oscar for Darling. Her latest nomination has done little to alter her perception of the statuette's value. "For me, being nominated is just a bit terrifying," she says, "because I think, 'Oh God, I hope I never have to get up and say anything.' "

But she has a plan in the event of victory: "If I win it will be put in a box in a room full of things I do not use. Things that I've appreciated but don't use."

Best-supporting figures

$100m

The amount teen pregnancy comedy 'Juno' has taken at the box office

4

The number of acting contenders who are Brits playing Americans

$1.8m

The amount advertisers have spent for each 30-second TV spot

20

The number of times sound technician Kevin O'Connell has been nominated; no wins yet

$130m

The economic boost that the Oscars are expected to give Los Angeles this year

82

The age of Hal Holbrook, who receives his first nomination for best-supporting actor

$7,500

The day rate for a top hairdresser to do an actress's hair for the 2008 Oscars