Watch the trailer for There Will Be Blood

When I walk in, Daniel Day-Lewis and Paul Thomas Anderson are out on the balcony of the hotel room, sharing a joke and quick hits off a cigarette. The affinity between the 50-year-old British actor and the 37-year-old American director is unlikely but palpable. They’re picking up where they left off when they finished shooting There Will Be Blood more than a year ago. They haven’t seen much of each other since – Day-Lewis lives in rural Ireland, Anderson in Los Angeles – but you sense their shared exhilaration after almost rapturous previews of the film. At the screening I’d seen the night before at the Writers Guild of America, the industry audience had given the film a standing ovation, a rare occurrence. One person said: “It feels like the first great American film of the 21st century. It tackles all the big themes about America: blood, oil, religion.”

It’s a harrowing, visceral, epic drama about the early years of the oil boom in California, and some drew comparisons to Giant, starring James Dean, which was shot at the same location, Marfa, in the southern Texas desert; others alluded to Citizen Kane, because of its focus on the corrosive effects of the pursuit of wealth. As the audience poured into the lobby, the talk was not of whether the film would be in the running for Oscars, but of how many nominations – including certain nods for Day-Lewis as best actor and Anderson as best director – it would get.

Loosely based on Upton Sinclair’s 1927 novel Oil!, There Will Be Blood is about the forces that created the wealth and power of industrial America, and those destroyed by it. But it is told as the microscopically intimate character study of one man: Daniel Plainview, a miner and oil prospector, played by Day-Lewis. His obsessive pursuit of wealth devours those closest to him and whatever there once was of his own soul. Like much of Anderson’s work, it is also about the relationships between sons and fathers. Here, he explores those Shakespearian themes through Plainview’s heartbreaking relationship with his own young son,played by a newcomer, Dillon Freasier, but also through his relationship with his young nemesis, a small-town preacher, wonderfully played by Paul Dano, last seen as the awkward brother in Little Miss Sunshine. The feverishly unsettling score, by Jonny Greenwood from Radiohead, also plays like a character in the film, clawing into your bones.

The savage power of the film, however, really derives from Day-Lewis. He plays the brutal, ruthless oil prospector with such ferocious intensity and demonic relish that, as the reviewer for Variety wrote: “It’s difficult to imagine him emerging between takes as just an actor playing a part.” According to people on the film – adding to Day-Lewis lore – the actor remained in character throughout the three-month shoot, on and off the set. Which, once you’ve spent 160 minutes in Plainview’s company, is a truly scary notion.

Luckily, as we talk today, Day-Lewis is back in his own skin. The actor, son of the late British poet laureate Cecil Day-Lewis, is tall and sinewy, always slightly pitched forward, his broken nose pulling to the left, ear lobes hung with thick gold hoops, lank hair now spotted with grey under a pork-pie hat. He has circular tattoos running down his forearm, and the tattooed handprints of his children on his upper arm. In person, he is a gracious, courtly and attentive man, quick to laugh. It’s hard to see where his reputation for dark moods might have come from.

Anderson, sitting nearby, is more tentative, almost boyish, his brown hair cut close to the sides of his head. Their closeness seems surprising. Where Day-Lewis’s conversation has an instinctually rich and poetic lilt, Anderson’s more awkward phrasing betrays his upbringing in the very different world of the San Fernando valley of Los Angeles, where most of his films have been set. Yet, as well as a taste for illicit nicotine, the two men share a seriousness of purpose, which is why they both work sparingly. Anderson has made only two films since he burst onto the scene 10 years ago with Boogie Nights, which was set in the crazed world of the valley’s porn industry: the sprawling Magnolia (1999), which starred Tom Cruise; and Punch-Drunk Love (2002), a comedy with Adam Sandler.

The first stirrings of There Will Be Blood came when Anderson bought a copy of Oil! in London because he was feeling homesick and liked the cover illustration of a California oilfield. “I was frustrated by the things I was writing, and had gotten sick of my own voice, and would sort of transcribe the book to see how it looked,” says Anderson, twice Oscar-nominated for best original screenplay, for Boogie Nights and Magnolia. “The book’s genesis was that Sinclair’s wife owned a plot of land in Signal Hill [just south of LA], where they found oil, and he got to witness this explosion, how the town fell apart.”

“Paul wrote it with Daniel in mind,” says JoAnne Sellar, the British producer behind all of Anderson’s films since Boogie Nights, “and we approached him when the script was about three-quarters done.” Day-Lewis, usually reticent about taking on new film projects, quickly agreed to come on board. Since 1997, the actor had made only three films: The Boxer; Martin Scorsese’s Gangs of New York, in which he played Bill “The Butcher”; and, in 2005, The Ballad of Jack and Rose, which was written and directed by his wife, Rebecca Miller. Day-Lewis and Miller married in 1996 and have two sons, aged nine and five. They met when he starred in the film version of The Crucible, by Miller’s father, the late playwright Arthur Miller.

Asked what spoke to him in the script, Day-Lewis says: “Paul, in the voice of Daniel Plainview... I know when I feel irrevocably drawn to something. Sometimes I take a step backward to try to assess whether I genuinely can be useful in telling that story – and sometimes I really feel I can’t be. But, once drawn in, I have no option but to follow that path, and I really don’t question why it is I need that at that particular moment, or why it needs me.” He admits that one of the reasons he doesn’t work more is that he needs “to believe in the inevitability of the piece of work that you cannot avoid doing” to be prised from home. “For me, from beginning to end, it was about 3½ years of my life invested in telling this story, so it had to be something I felt a pretty compelling need to be involved in.”

It’s also true, however, that, more than any other screen actor, he needs to inhabit his characters so completely that the prospect of such immersion must be daunting. “The intention is always the same,” he says of the way he works. “To try to discover life in its entirety, or at least create for yourself the illusion that you have, which might give you some chance of convincing other people of it. It’s the same thing each time, but it requires totally different work in the process of achieving that. You are set on a path that’s strewn with obstacles, but getting over them is the joy of the work. So it’s impossible to think in terms of difficulty: it all seems utterly impossible, but the pleasure is in trying to forge ahead anyway.”

As a man who nearly became a cabinetmaker rather than an actor, and has intermittently been apprenticed as a cobbler, Day-Lewis’s craftsman-like preparation is celebrated. Playing Christy Brown, who suffered from cerebral palsy but became a painter and writer, in the 1989 film My Left Foot (for which he won a best actor Oscar), Day-Lewis spent two months with cerebral-palsy sufferers, and remained in his wheelchair even in pubs and restaurants at night. For The Last of the Mohicans (1992), he learnt how to hunt animals and build a canoe. For Bill “The Butcher”, he worked cutting meat at a butcher’s shop and spent months learning how to throw the knives his character used to kill people. The director Martin Scorsese understands his need for immersion: “He’d rather not be distracted from his focus.”

For Daniel Plainview, as he does for most of his characters, Day-Lewis started with the voice. He asked Anderson to send him recordings of voices from the era: the huge canvas of the film stretches from the late 19th century to 1927. “I have a little old-fashioned recorder I use when I’m working,” he says. “I talk to myself a lot; I live in a rural place, and there’s not much else to do during the winter. So I would send Paul sample tapes of me talking to myself.” Anderson had also sent Day-Lewis a copy of The Treasure of the Sierra Madre, directed by John Huston, an important influence on the film, and documentaries on Huston, whose rich voice seeps into the character-isation, as if Plainview were a prototype for the sociopath Huston played in Polanski’s Chinatown.

When they started shooting, Anderson admits: “Daniel’s attack on the role was quite intimidating at first. But it became clear to me that it wasn’t anything outlandish or strange. He’s still in there, to the point where we can communicate. The misconception would be that it makes it harder to work with him, as a director, but it’s actually much, much easier. You always think, ‘My God, it would be great if that person could leap off the page and be right there and I could talk to him’ – and then you have it.”

There Will Be Blood differs from Anderson’s earlier films in that it’s an adaptation, it’s not set in the familiar world of the San Fernando valley, and it doesn’t include his usual troupe of actors. In addition, it took a long time to set up, because, Sellar says, it was hard to finance. “We did it on an incredibly small amount of money, though it was more than the average for an art film. The studios didn’t think it had the scope of a major picture.” That meant Anderson and Day-Lewis were working together for a long time before shooting started, so it became a far more collaborative process than Anderson was used to. As the film nears release, he feels uncomfortable about comparisons to Citizen Kane, but he’s pleased people feel it has the same tragic intensity. “One of the great things about Citizen Kane is that it just goes downhill,” he says. “There’s such satisfaction in watching that.”

Day-Lewis tries to brush aside suggestions that the film should primarily be read as a critique of America and American values, although that’s clearly part of its thrust. He prefers to see it in more personal terms: “What it takes to get power, as you sacrifice yourself, little by little, in pursuit of the thing you thought you needed, or felt you couldn’t live without, and then you only understand too late that you can’t retrieve your soul – it’s gone, it’s torn.

“I suppose, if I had anything in common with Plainview, it would be ‘the fever’ he has. With me, it just happens to be for my work – which is a kind of mining work, dark and sometimes unrewarding, but absolutely compelling.”

There Will Be Blood is released on February 8

To view the trailer for There Will Be Blood, go to timesonline.co.uk/film .

For full Oscars coverage, go to timesonline.co.uk/oscars

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