Mathieu Amalric is a man with the apparently limitless capacity to be exhaustingly profound. He does extreme thought like other people do extreme sports, so that he turns a simple question into an exercise in philosophical abstraction. 'How come I became an actor?' he muses, eyes gazing into the mid-distance, head tilted quizzically to one side. 'I was so shy. I still am afraid. I always think I'm not going to be able to do it. How can I learn these lines? How is the brain connected to the tongue? It's a miracle.' I nod. He smiles benignly, rather like, I imagine, Socrates might smile at Victoria Beckham.

Sometimes talking to Amalric can feel a bit like being in an earnest postgraduate discussion group pondering the meaning of it all. As an actor, too, he remains an enigma. He has a semi-recognisable face but, for the past few years, has contented himself with carving out a niche in critically acclaimed, independent films in his native France. Then last year he put in a startlingly good performance in Julian Schnabel's Oscar-nominatedThe Diving Bell and the Butterfly and shortly afterwards was cast as the baddie in the forthcoming Bond film starring Daniel Craig.

At 42, Amalric is teetering on the brink of global celebrity - but it is not a prospect he relishes.'I try to have a normal life,' he says. 'That's very important to me. Being an actor, if you only have that in your life, you would go mad immediately.' As he talks, he clutches his head in his hands, as if attempting to dig thoughts out with his dirty fingernails. 'Try to do things you're not able to do,' he says at one point, apropos of not very much, and then leans back in his capacious leather armchair with an enigmatic sigh.

It's impressive, in a baffling way. But perhaps it should not be surprising: as an actor, Amalric is extraordinarily good at conveying a sense of great depth of thought onscreen, even at moments of extreme physical passivity. His performance as a paralysed victim of 'locked-in syndrome' in The Diving Bell and the Butterfly won him a César for best actor. Amalric's portrayal of Jean-Dominique Bauby, the former editor of French Elle who was left paralysed by a massive stroke in 1995 and able only to blink his left eye, was remarkable for being almost entirely static, yet simultaneously conveying each subtle shade of poignancy and pain.

For an actor so defined by intellectual introspection, I wonder whether the machismo of Bond is not a come-down. He ponders this. 'You know, when you act, you act with your body, so immediately you're not working as an intellectual. You have to be an animal. You have to be a bit stupid to be an actor, it's very important, you know, just to be...'

Instinctive? 'Yes. It's exactly like an acrobat, I spend a lot of time preparing my props. TheJames Bond was a continuation [of that]. This morning I was rehearsing the stunts for the fights and I love that. It's very wild, very nasty - it's great. And you know for The Diving Bell and the Butterfly, I was exhausted by the end of the day. It's very physical, not moving.'

He can't say much more about Quantum of Solace, the 22nd Bond film due for release here in the autumn, because of the near-fanatical secrecy that surrounds the franchise. But he didn't hesitate when they asked him - for years his PIN was 0007, although I imagine he might change it now, in case any enterprising French criminals read this interview. Earlier this year, he spent weeks shooting the Bond film in Panama and he is full of praise for its director, Marc Foster: 'He understands actors.'

In his latest film, Heartbeat Detector, Amalric plunges into a similar blankness as a staff psychologist working for a Kafkaesque petrochemical corporation. The basic premise seems to be that corporate downsizing, with its dehumanising treatment of people as 'units', is analogous to the genocidal evil of the Second World War. Isn't that quite a leap of interpretation? 'It's trying to put two things together and seeing what happens but there's not really a theory in this film. There's just a dizzy...' he trails off. 'It's the use of language, of technical words that hide violence but make you do horrible things.'

For all the movie's flaws, Amalric's performance is once again notable for its delicate nuance - a chiaroscuro sketch in a gallery hung with blazing oils. At one point, Amalric is shown twitching uncomfortably as his boss inexplicably decides to relieve himself in the corner of his office. The camera focuses on the tiny details of Amalric's face - the pulsating muscle in his cheek, the half-frown of tension and embarrassment. 'You sort of drown yourself,' he says, choosing his words unfortunately. 'You forget you're acting.'

Amalric's office-peeing co-star was none other than Michael Lonsdale, an actor best known for his 1979 role as James Bond's nemesis Hugo Drax in Moonraker. Amalric asked for Lonsdale's advice before accepting the role of Dominic Greene, an ecological campaigner turned villain - think Jonathon Porritt with a psychotic streak. Lonsdale told Amalric that the pleasure of being a good actor was doing what people didn't expect. He took the role.

For all his undoubted talent, Amalric is at pains to point out that he never set out to be an actor. He was born in the wealthy Parisian suburb of Neuilly-sur-Seine and his parents were both journalists on Le Monde - his mother, Nicole, was a literary critic and his father, Jacques, the foreign affairs editor. He was never tempted to follow their lead - 'Perhaps I was too pretentious' - and says he knew from the age of 17 that he wanted not to act in films, but to direct them.

A family friend recommended him to Louis Malle who was then filming Au revoir les enfants and took Amalric on as a trainee assistant director in 1987. He confesses that he was too intimidated to speak to Malle: 'Shyness is a very bad thing in movies, you have to kill it - yes! You have to go take risks and you have to be unafraid of being thought ridiculous.'

In fact, his most vivid memory of the shoot was running into technicians in the editing suite who were working on Roman Polanski's Frantic, which was being filmed a few streets away. He admits he was 'fascinated' by Polanski at the time. He has been told that he looks like him and there is a clear resemblance - the same sleepless brown eyes, the same fluid mouth and an attractiveness that stops short of being uncomplicatedly good-looking. But there was a family connection too: Amalric's maternal grandparents came from the same Polish village as Polanski. They were Jewish and moved to France with Amalric's mother at the outbreak of the Second World War (Amalric also appears in Un secret, a Second World War drama about a Jewish family). Yet when I suggest this might have given his performance in Heartbeat Detector a personal aspect, he shies away from the question.

'Well yes, yes. In fact... yeah, when my mother dies, the name won't exist anymore because she is the only one left. The whole family died... but...' He grapples uncomfortably. 'I had no religious education, nothing. I feel Jewish sometimes when I watch a Woody Allen film.'

It seems a wilfully superficial answer, but it soon becomes clear he doesn't much like talking about his parents. They separated after Amalric left home ('It's complicated,' he says before firmly refusing to expand) and when he directed his first feature film in 1997, Mange ta soupe (Eat Your Soup), he loosely based the central family on his own. The mother character just happens to be an egocentric literary critic, submerged in a world of books. 'It's pure tragedy and I tried to do a comedy,' he smiles sadly. 'That's a bit Jewish.'

He now has three sons of his own - the two eldest, eight and 10, from his long-term relationship with the stage actress Jeanne Balibar - and the youngest, nine months, with his current girlfriend who is a playwright.

Now that he has his own family, does he feel that his parents are proud of him? 'Like all parents, you know it, you feel it, but they don't tell you. You hear it through friends. My father is retired, he lives in Corsica in a small village and I know that he's very proud because when I go there, people from the village tell me that he's talking about me all the time. But when I'm there he's like a bear, you know, he won't say anything.'

Amalric went on to direct a further two movies before being persuaded to accept his first major acting role, aged 30, in the cult French film Ma vie sexuelle. Then, he says, he just kept being offered acting parts by 'great directors' and it all got in the way of what he really wanted to do. At the moment, he has no fewer than six films in the pipeline. And then there's the one he wants to direct himself, about American burlesque dancers, which keeps getting postponed.

'I think my nightmare would be that maybe I'm just a good actor,' he says, laughing gently. 'But I love directing. I think about that all the time, but sometimes, maybe, you're better at something you don't care about. Gainsbourg didn't care about his songs, he wanted to be a painter. Nina Simone wanted to be a classical musician.'

He gives actors remarkably short shrift, which is refreshing. 'There's all this bullshit with actors,' he says. 'There's a lot of solitude and childish relationships with people. I couldn't be only an actor - you go mad immediately. It's crazy, you don't have any responsibility - people order your wine for you, they order your food, you want new socks and a driver, you want a ticket for a play tonight... there's this disconnect.'

His unactorly take on life is clearly a point of pride for him, but I can't help wondering whether he doesn't take it all a lot more seriously than he's willing to admit. There's the small matter of his clothes, for instance. At first glance, it seems they have been artlessly thrown on, as if Amalric had much more important things to worry about. Today he walks in with a scuffed rucksack slung over one shoulder, wearing a professorial corduroy jacket over an unexceptional jumper. Yet, on closer inspection, his outfit is revealed as carefully colour co-ordinated in precise shades of brown and black - from the stripes on his jumper down to his Le Coq Sportif trainers, which are black leather, with the logo picked out in matt bronze. Clearly, this is a man for whom detail is everything, but who doesn't want to look as if he tries too hard. At one point, talking about Heartbeat Detector, he says his character is 'maybe a bit too much obsessed with perfection'; Amalric could be talking about himself.

'He's got this chimeric sensitivity,' says Nicolas Klotz who directed him in Heartbeat Detector, when I talk to him a few days later. 'He knows that when we are most strong, we are also at our most fragile. I think he's obsessive but also very lucid, very precise and he also allows himself to be directed. He's child-like in that way: he has the confidence just to let himself go. He thinks deeply, but when he comes to work, it becomes a concrete task and because he is a director as well, he knows the problems and he's very attentive, very willing to be directed.'

Amalric has prepared for the Bond role with a similar thoroughness. He has thought a lot, he says, about how to be evil. 'Now that the Bonds are more realistic, you don't know who the villain is anymore - they don't have a metal jaw, they don't have a scar, they don't have an eye that bleeds. In this film, I don't have anything to help me be a villain; I just have my face. So maybe his weapon is his smile, like the mystery of the smile of Tony Blair.'

Or Nicolas Sarkozy, perhaps? At the mention of the S-word, Amalric becomes instantly irate, leaning into the table so that it judders slightly as he speaks.

'It's not a joke,' he says as if he's just witnessed me throwing a bucket of rotten tomatoes at an elderly woman in the street. 'It's very tough, very, very tough and it's only been one year that he's in power. It's finished. I mean, the belief people had in him is just dead. I have a lot of difficulty now to find that exotic or funny or ridiculous. I'm disgusted.'

He looks utterly stricken. It must be exhausting being Mathieu Almaric: the agonising analysis of each narrative twist and turn, the frustration that he's not doing quite what he wants, the stressful colour co-ordination demands of his wardrobe. And then, on top of it all, being forced to do interviews in your second language about the implications of the Holocaust and what he thinks of the baddies in James Bond. No wonder he has reservations about being an actor. But I wish, for a moment, he would stop taking it all so seriously. So I ask him to tell me his favourite joke. His eyes widen.

'Wow. The problem with jokes is you hear a great one and you say, "I won't forget this one" and then you just forget them.' He lapses into a long, effortful silence. 'There's a very short one, about a Jewish son who calls his mother. He says, "Hello, Mama, how are you?"

"Fine."

"Oh, sorry, I've got the wrong number."'

He delivers the punchline with a small smile. It's a good joke. I am glad he remembers it, if only to provide some light relief for both of us.

Heartbeat Detector opens on Friday

From birth to Bond: Amalric's progress

Early life

1965 Born 25 October in Neuilly-sur-Seine, a Parisian suburb. His Polish Jewish mother was a literary critic on Le Monde, his French father the paper's foreign affairs editor.

Career

1987 Taken on by Louis Malle as a trainee assistant director for the film Au revoir les enfants

1996 Took his first major acting role in Ma vie sexuelle for which he won his first César, for most promising actor (pictured below).

1997 Directed his first feature film Mange ta soupe, including a family loosely based on his own.

2008 Won a best actor César for his role in The Diving Bell and the Butterfly

2008 Plays ecologist-turned-villain Dominic Greene in the forthcoming Bond film, Quantum of Solace

Family Life

Has three sons, aged 10, eight and nine months; two by his former partner, the theatre actress Jeanne Balibar, and one by his current girlfriend.

Amalric on acting

'Acting is like a vengeance on adolescence, when you have spots, when you're too shy to invite a girl to dance. I need that sensation of getting away with something because it's exciting.'

And on playing in a Bond movie

'I couldn't resist it. My two boys, who are eight and 10 - I can't tell them one day that I refused to be the villain in a Bond movie.'
Ally Carnwath

Bond baddies: Top 007 villains

Dr No The 1962 original, arguably the most chilling of 007's foes. Dr Julius No, played by Joseph Wiseman, is a brilliant scientist with bionic metal hands and a taste for stolen art.

Goldfinger (1964) Played by German actor Gert Fröbe and voiced by Michael Collins, Auric Goldfinger plans to contaminate US gold reserves with a dirty bomb. He delivers one of the great Bond lines: 'Do you expect me to talk?' says a trussed-up Sean Connery. 'No Mr Bond, I expect you to die.'

Blofelf The cat-stroking head of Spectre, an international criminal organisation, features in seven Bond films. His best-known incarnation is played by Donald Pleasence in You Only Live Twice.

Rosa Klebb Klebb (Lotte Lenya) appears in From Russia With Love (1963) as a high-ranking Spectre agent who attempts to kill Bond with a poison-tipped blade in her shoe.

Scaramanga In the 1974 film, Francisco Scaramanga (Christopher Lee) is the titular Man With the Golden Gun who lures Bond into an elaborate shoot-to-kill duel.

Elliot Carver Jonathan Pryce plays the media mogul in Tomorrow Never Dies (1997), plotting to increase circulation and audience figures by provoking a war in the South China Sea.
AC

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