The sofa is vibrating. Brrrr . . . brrrr. It feels as if an extremely large, extremely low-frequency mobile phone is hiding under the cushions. Except it’s not. It’s Ben Whishaw’s leg. The 27-year-old actor twists and wriggles, turns and writhes, as we discuss his latest film: an adaptation of Brideshead Revisited in which he plays the louche, affected, teddy bear-carrying Sebastian Flyte.

The sexually ambiguous lord is just his latest role in a career stocked with doomed, tragic youths, from Hamlet at the Old Vic in 2004 to a man accused of murder in the BBC drama Criminal Justice this summer. For Hamlet, Whishaw was fêted as one of the greats of the stage. For Criminal Justice, he was praised for his “haunting, wraith-like aura”. But the Brideshead film has invigorated another sort of critic: the sort who considers messing with Evelyn Waugh to be messing with English literature itself.

“I guess it has offended some purists,” Whishaw says suddenly, unprompted, and apparently unperturbed by the idea. The new adaptation plays with chronology, losing some themes, accentuating others, and seems guaranteed to bait those who expect their classics to remain unviolated.

Critics in America, where the film is on general release, have already deployed their thesauruses. The New York Times called it “tedious, confused and banal . . . a lazy, complacent film which takes the novel’s name in vain”, attacking it not just for missing the subtlety of the book but also that of the 1981 drama starring Jeremy Irons. “You know what, I’m happy to have a fight about this,” Whishaw says, cheerfully. “It needn’t be a bad thing that we had to compress it: that can work in your favour — I don’t think it’s necessarily a loss to have to lose things. I think the screenwriters very skilfully joined the two halves of the book.”

The attacks do seem unfair: whatever the screenwriters had produced, anything short of a word-for-word facsimile of the novel was likely to offend. Taken on its own terms, though, this is a fun, intelligent and spectacularly beautiful film. But there is a more existential difficulty. “I have been thinking a lot recently about the question ‘why do it at all?’, particularly since it has been done well before,” Whishaw says, referring to the ITV adaptation. “I guess that what is interesting about these period films is that they are not really period at all. They completely speak of the time they made it. The mini-series of Brideshead probably tells us a lot about 1980s Britain.”

And this latest adaptation? What does it tell us about today? Hunched over his coffee cup, Whishaw makes rare eye contact and says: “Oh God, I don’t know. Maybe I should watch the film.” But that’s another problem: he doesn’t like seeing himself on the screen, and generally avoids his own movies.

“I don’t get anything from it,” he explains later, twiddling his hair. “I see all sorts of horrible elements of myself, like vanity, come to the fore.” He claims still not to have watched I’m Not There, the 2007 film in which he played one of seven Bob Dylans (the screenplay was, he says “totally f***ing bonkers. Mind you, Bob Dylan is bonkers, too, so he can get away with it.”).

There is so much Whishaw says that should sound affected. He says his “only ambition is to get better at acting;” he “never wanted to be a star, or a personality”. He describes Hamlet as “such a work of genius that no one can do it justice”. This sounds like the gushings of a thesp, but he is sitting on a sofa, wriggling and fiddling, moving his head sparrow-like.

If this is affectation then he is, well, a very good actor. Whishaw grew up in Clifton, Bedfordshire, in a family with no acting pedigree. His parents were, he says, “slightly bemused, but extremely supportive” of his childhood acting dream, helping him to work his way through the local drama groups. He now says that the hardest part of playing Sebastian was not the apparent homosexuality but the Catholicism and the aristocratic elements. “They are totally alien to me,” he says. “And the concept of things like sin, damnation and Hell? My family was not at all religious.”

As a teenager he actually played Hamlet twice before his breakthrough casting. An early role was starring, at 15, in a production on the Edinburgh Fringe of Primo Levi’s If This Is a Man. But still acting did not seem a viable goal until he had almost achieved it. “I am lucky, very lucky,” he says. “I didn’t even think I’d get into drama school; I thought ‘maybe I’ll be an actor if they accept me’. Eventually I found other people who were actors. But as a kid it wasn’t something you could see a path towards.”

This is where the conventional narrative begins. Whishaw won a place at RADA and, a year out of college, was signed up to play the Old Vic’s youngest Hamlet. He may claim never to read his reviews, but parents are immune from such high-minded scruples. After the first night his mum rang him up to tell him that he was on the front page of a national paper. The performance was spectacular: the critics declared him one of the immortals, Whishaw had finally arrived.

But the critics were far from unanimous. Some considered him wonderful, some hit-and-miss, others merely competent. There was enough praise for the offers to start coming, but his career was far from assured.

He has been working hard ever since – perhaps too hard. “I’m not feeling driven and excited by work: suddenly I find I’m slightly indifferent to it, which is alarming,” he says, blaming it on tiredness. But later he says he might one day leave acting altogether. “I still think I’ll do something else at some point,” he says. “I don’t like the feeling of my life not being mine, and of other people having the power to make decisions about my future. Because once you start building a career a lot of people want to tell you what to do.” His future plans don’t include work at all but a trip to Australia.

Interviewing Whishaw is hard. It’s not that he is impolite or uppity; he is charming and casual. It’s not that he is cagey. But he quite obviously (and by his own admission) hates the whole process.

Later, playing back my recording, it sounds like a parody of an awkward dinner party. The clinking of a teaspoon, silences and long pauses. Midway through a sentence Whishaw might stop for ten seconds to consider his answer. Then there’s the wriggling. Previous interviewers have searched for meaning in his twitching. Is it the nervous energy that feeds his acting ability? Or the restlessness that drives him to new characters? Or maybe it’s just what he does.

A clip on YouTube shows Whishaw appearing on Richard & Judy. He sits on the sofa, visibly and increasingly uncomfortable, as Richard Madeley launches into a rising (if endearing) crescendo of praise for Whishaw’s talents, before asking him what makes him “very simply, very good”. “Is it self-belief?” Madeley asks. “Is it total belief that you are that person?” Eventually Whishaw murmurs something about acting being cathartic, before adding: “It’s not something I would ponder too much really”.

At the mention of the clip, Whishaw gurns – sticking out his tongue and holding his head at an awkward angle. “You can’t really get into these questions. ‘What drives you?’ Jesus, I don’t know.” He looks at me. Pause. One, two, three, four seconds. “I need a wee,” he says, and dashes out. Leaving the hotel together, we talk about other things: about things other than Ben Whishaw. And suddenly conversation is easy.

Brideshead Revisited is released on Oct 3 2008

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