Robert Carlyle is one of the most versatile actors of his generation, inhabiting psycho, soft touch, lover or loafer so convincingly that people often fail to realise it's the same man. He's a performer with perfect pitch, the star of Trainspotting and The Full Monty, two of the most commercially successful British films of the last decade. And he co-ordinates his international acting career from his native Glasgow. Carlyle is fiercely private and an avowed enemy of the press. His public persona is similarly fractured: garrulous hardnut, working-class hero, fanciable chancer, nippy sweetie. Committer of the cardinal celebrity sin of taking his work seriously.
So here is Carlyle today. "I appreciate my life and what I've got in my life. It's always good to remind yourself, wherever you go. Me and Anastasia [his wife] are sitting there and I'm like, `F---'s sake, babe, this isn't bad'. I'm a very lucky man. I'm always grateful."
Nothing about him is obvious. There are qualities that you sense rather than intellectualise: warmth, intelligence, honesty, cheek. He is preternatually elusive. But his body can't dissemble - it coughs at awkward questions, leans into interest, coils round a joke.
Thirty-nine-year-old Carlyle's latest endeavour is There's Only One Jimmy Grimble, a gentle urban fable charting the journey of a lonely Manchester City fan from playground punchbag for the rival Reds to schools' cup final hero. Alongside Gina McKee and Ray Winstone, Carlyle turns in a typically nuanced performance as Eric Wirral, Jimmy's games teacher. "I just felt for that kid. Bullying is a terrible, terrible thing. It would be nice if any kids in that situation come to see the film and get a wee boost," he says eagerly. "That's idealism at its best. It's only a f------ movie, but hopefully that's what it's about."
In the debut feature film of television director John Hay, Carlyle's part was the antithesis of his last role as osprey-wielding Bond villain Renard in the $110m blockbuster The World is Not Enough. "I had a great time doing Bond, but it was an alien world. I wanted to get back to the type of films that I feel comfortable making, and that I think have some kind of social worth. You take the $105m off and you can focus a wee bit more."
"There's been a lot of aggression [in my recent work]. I didn't ever want to be seen as that, but I know I've got that reputation. I wanted to redress that balance. I've stabbed, punched, eaten people, blown them up in films for ages. I saw something in this that I needed for myself. It was very calm - an antidote for myself in a way."
Most of Grimble's youthful cast are first-time screen actors. "Acting is a really insular thing. You're in this vacuum, and working with teenagers shakes you out of that because you realise your responsibility is to make sure they're OK. You can pass on what you've learned, and that's one of the most rewarding things that you can do." It could sound horribly Miss World were it not for the fact that it's delivered with such enthusiasm. Doesn't Carlyle have a tendency to put himself in that vacuum? His thoroughness is legendary: learning to drive a double-decker bus for British director Ken Loach's Carla's Song, sleeping on the streets in preparation for Antonia Bird's Safe. But it's clean of pretension. "To me, it's a simple thing. The people who employ me are putting their faith in me and paying me to do a job. I don't know whether it's a west of Scotland work ethic or whatever, but I feel that it's my responsibility to fulfil that for them. For those three months my life goes on hold and that seems to me to be a fair exchange for me to be able to do what I do."
The belief of others - as much as self-belief - seems to be very important to Robert Carlyle. The last thing anyone expects is success, he says. He talks especially tenderly about Antonia Bird's early faith in his work. Now a close friend - they set up a production company, 4Way Pictures, together with Mark Cousins, former director of the Edinburgh Film Festival - she first cast him as Safe's homeless psychotic Nosty in 1993. "Antonia believed in me when nobody did. I'll never ever forget that. She's a good woman."
His ego is modest but not fragile. If a criticism of his work is offered, he is interested to hear it, all the while making it clear that he privately maintains a complete understanding of why you are wrong. If Jimmy Grimble is about the grim realities of childhood, it is also about the stories we tell ourselves that allow us to escape. What were the stories Carlyle told himself as a child? "I was always a dreamer. You couldn't keep me away from the cinema when I was a kid - I lived in the Wild West completely. When I got to 21 and I was introduced to acting again, I didn't equate the images I'd seen as a child with the theatre - it didn't seem to me to be the same world." Why didn't the theatre move him? "I never believed it. I never believed myself. It's too artificial. You could say it's artificial on a film set, but when I'm in a room, in a tight situation and the camera's pretty close, I don't see anything else but the other actor I'm looking at."
Carlyle's transition from tradesman to thespian is well documented, perhaps because it's one of the few stories he'll tell about himself: money left over on his birthday book token, he chanced upon a copy of The Crucible and was hooked. He stood out at the Royal Scottish Academy of Music and Drama; and formed a theatre company called Raindog taking plays to local communities, before Loach gave him his first big break, in Riff Raff. He nods his head mockdoltishly when I recount it back to him. There must have been more, though.
"Put it into the political context of the time. The Thatcher years were beginning to bite really deep in the late 1970s, jobs were vanishing and so leisure time for people was growing and growing.
"Acting, the arts in general, is a magnet for the wounded of society. A lot of people that came to the arts centre I went to never had any intention of going on to a career in acting, but socially they got a lot out of it, talking to people who weren't going to laugh at them, being in an environment where they could maybe get a bit of shit out of their head. They could rail against society in the safety of the rehearsal room. I became a more political person inside my own head about that time." And he placed his social situation in context for the first time.
Born in 1961, in Glasgow's Maryhill, Carlyle was brought up by his father Joseph, a painter and decorator who lived an itinerant lifestyle but was based in Scotland. (His mother left when Carlyle was a toddler - he had no contact with her until the British tabloid the Sunday Mirror tracked her down in 1995: "I didn't even know what she looked like, and then these bastards dug her up. Imagine what that does to you," he said at the time.)
The British Labour Party's election defeat in 1992 crushed his faith in party politics. "I turned my back on that. Social politics is a different thing. I still care about how people are treated."
Do those politics still inform his choices? His projects span a broad spectrum of issues: Priest was about homosexuality, the British TV series Hamish Macbeth starred a dope-smoking copper, The Full Monty touched on the decline of the steel industry. He hesitates. "Everything inside me wants to say yes, but it isn't true. Bond, or Plunkett and Macleane, these films aren't anything to do with that. They're entertainment. I don't have any qualms about it. But, if I can, and if the choice is there, nine times out of 10 I'll go the other way."
He is happy: his home is in Glasgow with his wife of three years; on trips to London, he hangs out with his pal Ray Winstone; and has a tight group of family and friends. It keeps him grounded, he says.
What do they think of him in Glasgow? He wriggles in embarrassment: "I think they like what I do. I think there is that sense in Glasgow that `he's one of us'. I don't revel in it, but I like that, because that's what I've always wanted.
"Whenever I did anything, particularly in this tongue, I didn't want anybody to go, `That's shite, by the way, that's not true.' I think that so far, whenever I've been asked to interpret any Scot in any way, I've told it as it is and I've sounded the way they are. I don't think I've caricatured."
For someone who prides himself on withholding from interviewers, he does a good act of being forthcoming, I say. "I think I've gone so far down this road now I can't come back. But I think it's vital that you keep a bit of yourself back, you have to try and retain a bit of mystery. There's wee things, wee secrets that you have to keep back. Then you're always capable of surprising people. If your face is in the paper every day it's no good. It's boring. It disempowers you."
Carlyle once railed against a journalist for suggesting that the actor's life informed his work. But surely some universal experiences do? "Personal life is different from experience," he says. "Whether it's my childhood or whatever, for someone to equate that with what I do as an actor is up to them, but it's too convenient to say it's because he grew up like this, that's why he's like that. How pat is that notion? There are a lot of things that make up a performance, a lot of technical things. It isn't always just about pulling it up from the darkest recesses of your mind or your heart. It's your experience, and your observation. Because sometimes I'm looking at this guy in a bar and I'm watching how he's putting a glass down."
He demonstrates with the water on the table. "Normally, you'd put it down so. But Trainspotting's pub-psycho Begbie, for example, would put it down so." It's a small action. He hardly moves. He's not even looking at me. But, just for a moment, I'm in a room with a loony.
There's Only One Jimmy Grimble opens on August 25th