As anyone who's seen his movies knows, Ewan McGregor has nothing to hide. But will the star of the new Star Wars movie draw the curtain once the giant rats of fame come scratching at his door?

Ewan McGregor is dreaming about rats. Giant mutant rats with yellowed teeth and crusty, mottled fur. He wants to kill them, to smash them dead but he can't. They just keep coming, each one larger than the next, eddying around his feet, nipping and hissing. "And then my mom was there," he says, reliving the nightmare, cringing a bit in his backstage dressing room, "and she finally bashed one on its back with a baseball bat, broke its head, fucking killed it.

It's January, dusk, an hour before McGregor is due onstage as Scrawdyke in Little Malcolm and His Struggle Against the Eunuchs at London's Comedy Theater. He is taking a breather from films, having done fifteen in five years, a manic pace by any definition. The play, which drew mixed reviews but sellout crowds, is, like much of McGregor's work, "an interesting look at young men and what they get up to." McGregor offers a solid performance as the rogue leader of an aborted rebellion, but he really comes to life when the curtain drops. Satisfaction floods his face, and he exudes a compelling radiance, his jaw dropping into an open grin, his eyes way past jiggy with it. "I haven't been onstage since '92, and I love it. But I love the curtain calls most. I'm me again. I'm not trapped in that crazy guy. It's done. What a relief." The anxiety is part of the juice. "I did the show because I wanted to remember what it's like being totally frightened again. The fear of being crap is always what makes you good."

One of his costars in the play has suggested that the recurring night terrors are a foreshadowing of the 28-year-old actor's impending idolatry, his inevitable transition from quasi-obscure indie kid to mass-culture side order thanks to his starring role as the young Obi-Wan Kenobi is Star Wars: Episode I - The Phantom Menace. The film, which opens on May 21, is the first of the three planned prequels to Star Wars. It was shot in Tunisia, Britain and Italy over three and a half months and revolves around the rise of the Empire and the corruption of mop-headed Anakin Skywalker, the nascent Darth Vader. Plot detail are vigilantly guarded, and even the cast has yet to see the film. Such secrecy has only fed anticipation. "Suddenly, all these people are coming to me with posters to sign," McGregor says with disbelief, his Scottish burr tempered by his ten-year stay in England. " 'May the Force be you.' People have actually said that to me. 'May the Force be you, Ewan.' " He pauses, widens his eyes. "I think that's quite batty." He laughs, makes a face. "It's coming out soon, isn't it? Fuck. It might be a bit mad, eh? There are some scary people in the world, aren't there? They're fanatics. It's quite a scary idea."

The Phantom Menace may seem an odd choice for an actor who prides himself on making mostly low-budget films, but, as he explains, "Star Wars? How could I say no?" In fact, McGregor said yes twice, having also signed on for the next installment. "We looked at a lot of people," explains George Lucas, "but he came out best. The chemistry was there with the other cast members, and he gave his heart and soul. I'd been very impressed with Transpotting."

The sequel to Menace starts filming in 2000. "I may not come back," McGregor jokes. "I really do have rats in my flat. You open the door in the night to have a pee, there'll be one there, only now he's eight feet tall, looking you in the eye, saying, 'May the Force be with you.' "

Ewan McGregor has a reputation. Rumor is he's a drinker, a partyer, a flibbertigibbety, float-in, float-out, float-on kind of fellow. The thing you expect is that he'll be a lad's lad. That he will swill pints and stub out cigarettes and banter and piss his name in the snow and wave his pecker with youthful exuberance. He displays it frequently - in films, at home, at fashion shows in Milan. Make no mistake: This is a man who likes his penis.

And at a time when everyone feels he's being watched, or hopes he is, and grooms himself accordingly, the rumors are true. McGregor is one of those rare individuals - an aberration unheard of among thespians - who are born with a nearly complete lack of self-consciousness. He never seems to fret about how he's coming off.

He is, for one thing, chronically late. Not in a malicious, screw-you, diva-trip kind of way. More in a three-pints-later, "Oh, bloody hell," looking-at-his-watch kind of way. He is also not much for presentation. Unlike other young-dude actors, who carefully plan their unkept look, McGregor really just thrown on whatever he trips over on the floor, blows his nose on his sleeve and shuffles out the door, late. One suspects he eats breakfast naked, leaves the bathroom door open, that sort of thing, and if one really wonders, one can ask, and McGregor will answer or tell you it's none of your feckin' business. He is both open and protective, as he is of his wife, Eve, a French production designer, and daughter, Clara, age 3, whom he brings to movie sets to keep the family intact.

And then there is his career, which has garnered McGregor both critical kudos and a salivating following. Few actors are versatile enough to pull off period fop, as McGregor did in Emma, local bloke - Little Voice, Brassed Off - and human canvas, in The Pillow Book, auteur Peter Greenaway's erotic collage. McGregor spends most of that picture being painted in the buff. "He's the character I'm most like," jokes McGregor, "except I'm not bisexual or an intellectual.

It takes guts (and a healthy affinity for exhibitionism) to stroll about naked and more guts to choose parts you like, in small films for chump money, flipping the big finger to Hollywood, but McGregor has not been shy about much in his career. "Not having box-office success has never bothered me at all. I'm happy doing a film that will never be seen, working with first-time directors. I've worked with experienced directors, sore really bad ones, directors whose main concern is looking good on the set, looking in charge. I've worked with a lot of scared men. And the film looks like a pile of shit at the end of the day."

McGregor's pluck shows in his performances as well. In Velvet Goldmine, Todd Hayne's glam-rock tribute, McGregor steals the film in a brief onstage sequence, where his character, a gay, Iggy Pop-like rock-and-roll hoodlum, douses himself with some unlabeled viscous liquid, convulses, drops trou, flashes his sphincter and snarls an earsplitting "Fuck off!" "I never worry about how I'm perceived," says McGregor. Indeed, he spends his life in action, doing, not reading ("I think Shakespeare is all rather silly. I don't believe any of it") or listening ("I've never been very specific about my tastes") or thinking really about too much, but racing from scene to scene in a blur of good intentions, apologies and accidental charm. He is a perfect marriage of era and personality. A modified bad boy - motorbikes, yes; heroin, no - a rebel we can all comfortably like. Which is why he can play unabashed losers like Trainspotting's junk fiend Mark Renton or Goldmine's dirtybird pop star without losing our sympathy. You never dislike a McGregor character. Even when he's climbing out of a festering toilet, he stays accessible, just a guy having a rough go of it but he'll come through in the end.

Says Lucas, "Ewan knows how to make a line believable, to make it sound fresh. He makes things, even absurd things, seem real." McGregor explains it another way. "I like doing what I do. I find it amusing and funny and ultimately quite entertaining. Too many actors make it confusing and complex, and it's boring if you're like that. It's really quite a laugh." Especially when your horn is hanging out.

"I was doing one interview, and we were talking about my dick, which always crops up," he says, alluding to his propensity to select parts that require he flash his. "And I said flippantly, 'Well, I have a very large penis,' like a little joke. And then two months later, in a magazine that had bought the interview, above my head in quotes, it says, 'Yes, I have a very huge penis!' " He laughs. "I looked like such a cunt." Not that he cared. "What's the point of doing an interview, of doing anything, if you're going to worry about saying the right thing?"

Here is the part where he lights a cigarette. He will light many, because "I smoke a lot. I drink far too much. I torture small animals. I don't exercise," and because it amuses him when reporters take note of his inhalation. " 'He drew another cigarette to his lips,' " he jokes, drawing another cigarette to his lips. "Why is that interesting? It's either that or talk about my penis." Which, some might argue, is more interesting than a pack of Marlboros.

But now he is on a rant. Not a bitter teeth grinder. More of a goofy, cranky, "and another thing" fuss. Even in ire, McGregor stays amiable. "I don't really do talk shows. I don't like the people that interview you. Most of the hosts use their guests to make themselves look clever. I fucking hate that. Letterman is such a bastard." He retreats, follows the gibe with a joke. "No he's not. He's a really nice guy. I don't like the way he interviews people. Same with Leno. Showing people up. Really successful Hollywood movie stars cringing in their seats at the mercy of these rather arrogant and uninteresting men."

He lights a, well, you know.

And another thing. "I have to do drug tests before movies, and I find that's quite out of order. Not because I'm a drug addict and I don't want to be found out, but because it's actually nobody's fucking business. When you're making films, you've got no life, and so you go out and get drunk at the end of the week, and then you have to take a drug test. I should be able to buy a bottle o Champagne and drink it all myself if I chose to. More and more of the wrong people are in power in movies. Insurance people, studio bosses, uncreative, rich, fat businessmen. I get notes from studio heads. 'He's not acting enough. Suggest that he act more.' There must be a kind of Nirvana somewhere where you can creatively make movies with the money you need without all the hassle."

Fresh cigarette. Big exhale. "I'm on a bit of a moan. But, you know, I'm really happy. I like people a lot." So you're a people's person? "I don't know what I am." He pauses, lights up, grins. "A wanker"

To understand McGregor, it helps to understand Hogmanay, the Scottish New Year's Eve celebration. Come December 31 in Scotland, the entire country erupts into a frenzy of unchecked optimism. Midnight hits, and after a rousing chorus of "Auld Lang Syne," the kissing starts. Ceaseless kissing. Strangers snog strangers; boys snog girls who snog girls who snog boys. Massive, anonymous making out that lasts for hours and is interrupted only by fisticuffs and drinking, which the Scots do, as McGregor explains, "to complete elasticity." The night holds limitless possibilities for exhilaration, the whole country sloshing along on an immutable, uncontemplative, guiltfree high.

The Scottish, contends McGregor, are a "happy, emotional people." And certainly during Hogmanay no one worries about anything. Everyone is so in the moment, so quiveringly present, lips puckered, kilts lifted, buttocks bared, pointless resolutions shunted off to more neurotic cultures.

"It's quite emotionally packed," says McGregor. "In London nobody bothers. I'm always going around kissing everybody, and it's two past midnight and everyone is already back to talking about what they're wearing. And I'm like a rocket trying to go off in the corner."

It's an energy he channels, because unlike many of the boys he grew up with, McGregor considers himself "very bad in a fight. In Scotland fighting is a pastime. You get really drunk and then have a fight. That's a night out. But I'd run a mile if one ever happened. I can talk a good fight," he laughs. "And I had a fight once, but I just got punched to the floor and that was it. I have male fantasies about fighting, when you're really justified in beating the shit out of someone. But I would never do it for a laugh." He pauses, then reconsiders. "Violence is not pleasant, but if someone was really asking for a good kicking, it'd be great to give him one."

McGregor was raised in the verdant bosom of Crieff, Scotland, population 5,500, the second son of happily married middle-class parents. His father and mother, childhood sweethearts, both taught school. His older brother, Colin, now a pilot for the RAF, was the sporty achiever. Ewan was the bohemian-to-be. His was a sanguine coming-of-age: Olivia Newton-John posters on his wall, a lame Billy Idol haircut, cigarettes at the bus stop, lunatic levels of masturbation.

McGregor experimented little, never with drugs, occasionally with girls, more often with fashion - tight striped pants, ripped sweaters, copious amounts of hair gel. "I was never a punk or a mod, because the town was too small. You'd be the only punk in town, and you'd have to hang around the street on your own being the only punk, and it would be really dreary.

Instead, McGregor watched movies. "My favorite films were from the '30s and '40s. They were unashamedly romantic. I don't like these cynical romances these days; they make such a ridiculous effort. Back then it was done with so much more aplomb and skill."

He also watched the Star Wars movies and, like every other young boy, was swept away by the mythic tide of franchise. Even more so since his uncle, the actor Denis Lawson, had a bit part in the series, playing Wedge Antilles, a rebel pilot. It seemed to McGregor that Lawson lived a wildly enviable life, driving around in Cadillacs, sporting hippie clothes and long hair. So at 16, Ewan quit school (with his parents' approval) and devoted himself to theater. He left home and worked at the Perth Theater for six months, went to drama school at the Kirkcaldy College of Technology, then moved to London, where he joined the Guildhall School of Music & Drama. Aided by his unappeasable drive and his appalling lack of self-doubt, McGregor succeeded.

He snagged his first part a half year before graduation, the lead in a British television miniseries called Lipstick on Your Collar. It flopped. He didn't. A role in another series, Scarlet and Black, led to bit parts in films, which in turn led to Shallow Grave, made by the same precocious team that would make Trainspotting, which would turn McGregor, three short years later, into a star.

"I don't have much fear about anything," he says. Then he thinks a minute. "Oh, well, very small places. Being buried alive. I wouldn't like that. There's that scene in that vampire movie with Brad Pitt and Tom Cruise wherein Brad Pitt gets put into a coffin and stood upside down and walled in. That would freak me out."

He also has "no regrets, not really. I can think of things I wish I hadn't done, but at the same time, if I hadn't, I wouldn't be who I am now. I used to be really guilt-ridden and regretful, and in fact, that's such a waste of time."

"Ewan is always overflowing with energy," says Liam Neeson, who plays Jedi mentor Qui-Gon Jinn to Ewan's Obi-Wan. "He's very spontaneous, very in the moment. That's a rare quality. It's an American actor's quality."

The two imports spent much of the Phantom shoot cutting up in the Tunisian desert. "We got on well," says Neeson. "When we first started fighting with the lightsabers, we made all these sound effects. We had the 11-year-old-boy syndrome." The stints were grueling, but McGregor was a fast study. "We had to learn six or seven moves at a time, and Ewan was rapier quick. He got onto it with phenomenal speed."

Since the Phantom publicity machine cranked up four months ago, Neeson has been forced to use an alias, a precaution he never needed before. "I got all these people calling me everywhere, saying, 'Hey, dude, are you a Jedi Master or what?' There's something about Star Wars that taps into the psyche of the whole world."

Neeson knows that McGregor, "a unique and handsome fellow," isn't hip to the fame game or aware of the explosion that waits ahead. "Star Wars is going to open a megabig door in America for Ewan," says Neeson. He knows there will be a riptide of publicity, that drowning will be a hazard. "Ewan has been spreading himself too thin. He needs to pull back and pick and choose a little more now or he'll risk burning out."

McGregor agrees, but he can't slow down. "I was going mad making films all the time. Being successful in film, I love it, but it's an abnormal way of life. I keep saying I'll take a break, but I don't. There's such good work about. And I have to be in everything that's made."

If you look at him, really look, you notice that McGregor is ugly-pretty. So much about his face is context, angle. In certain light, he is radiant, a dewy fruit of a man with a dirty grin and a broad forehead. Shift him a little and he transforms into a spotty lad with greasy hair and a mushy jawline. As such, he is nonthreateningly sexy. He's no Sean Connery. If you passed him on the street, you would pass him on the street, an everyday bloke in a crumpled woolly sweater and beat-up sneakers. The pursuit of glamour confuses him. "The women in L.A., the old ladies, fucking hell. They're really scary, aren't they? Someone should tell them, 'You don't look any younger. You just look really tight and uncomfortable and weird. Why are your ears in the back of your head? You're all going to die. Everyone is going to die.' But the most staggering thing in L.A. is seeing people walking on machines in the window of a shop, like they were on sale, like a slave market or something. 'Gay man for sale,' "

Which leads him to another observation. "I tend not to like people who are enthralled with fame." He explains. "That's boring. I find those people difficult to work with. That's why there's Jerry Springer. Because the need to be on television is terrifying. Some guy murders his wife to get on Crimewatch U.K. People do extreme things to get on television, don't they? Sucking off the president, stuff like that."

Hollywood bores him, sort of. "I don't care about Oscars. It's such self-aggrandizing nonsense. It's a way to manipulate people into believing that their choices are what's good. It's rubbish. They're looking after themselves. I'll be fucking deliriously happy if I ever get one, by the way. I'll go up there and cry and everything. But I don't value them, because I don't have one yet."

Whether he gets one or not, the wheel will continue to grind forward. It's a family trait. "My grandmother is 75 and still runs her own business. She walks to work. She'll dance till four in the morning. She's amazing, that woman. 'What are we going to do for the minnellium?' That's what she calls it: 'minnellium.' 'Decapitated coffee.' She's brilliant. She'll never slow down. I'm a bit like her, I guess."

When McGregor is not working, which isn't often, he is either snuggling with his family in his London flat or gunning pell-mell to hell on his motorcycle.

"I always slow down mentally on my bike. When you race bikes around country roads, there's no room for anything else but the road, the bike and you. Everything else goes away. It's like meditation. Only it's not like meditation, because you're going really fast and it's really noisy." He laughs, exhilarated by a memory. "I almost killed myself once. I came very close to hitting a car. I threw myself into a corner too fast, and I thought it was a shorter corner than it was, so I was drifting toward the middle, and there was a car coming the other way, and I remember the guy's face. I just made it, and it really scared the shit out of me, because I thought that was it." He slowed down then. For about twenty minutes. "Motorcycling is my passion. I can't tell you how good it feels. It's frightening, but I'm quite impressed with myself when I'm doing it. I've always loved motorbikes. Maybe it comes from Elvis Presley movies. They're quite cool, aren't they?"

McGregor craves speed. He's a tad manic. He "wasted no time" getting married and getting his bride "up the stick." He makes movies back to back. He drives fast and eats fast and exists in a palpable cloud of buzzing energy. Change does not frighten McGregor.

When asked about why he chose to get married so young, at 24, McGregor says, "I got married because I wanted to get married." When asked if he found such a heavy commitment off-putting, McGregor says, "I never look back and say, 'Oh, my life used to be like this and now it's like this.' I don't understand what the transition is. I don't know what changes other than that you're married. Having a child is a much bigger thing. Such an emotional, life-changing thing. Seeing my daughter asleep. Waking up half the night. You wear a hole in your carpet circling your flat with this screaming wee bundle. It looks like they're going to explode, but they smell so great. The smell of your baby's breath when they're screaming is so beautiful."

McGregor believes in family. He changes nappies and walks the rounds and tells his wife she's beautiful when she needs to hear it. Aside from family and himself, he is not a big believer in much. And he doesn't trust those who adhere to the Word, be it the Lord's, Buddha's or Darth Vader's. "I don't necessarily get on with religious people. It's too comfortable in a way to believe that somebody else is in charge and destiny is all planned out and we're all redundant. I can't accept that. I think we're in charge. I don't like people coming up to me in the tube and asking me what God thinks of my life today. Fuck off. How dare you ask me anything? I don't know - morality and rules, I don't really go for that sort of thing." So it's true, his reputation for being a bit feral, the family man with a wild hair? He grins. "It annoys me when people say things that aren't true. But being reckless is fine. I quite like being reckless."

Here is what else Ewan McGregor likes: Sushi. Duck. Cameron Diaz (his costar in A Life Less Ordinary). Beer. Singing. Golf. Martin Donovan. Steve McQueen. Chet Baker. Oasis. Cameron Diaz. Eddie Izzard. American cars from the '60s. That guy who did sex, lies and videotape, that guy with the camera. Yeah, James Spader. Motorcycling. Jimmy Stewart. And De Niro. Of course De Niro. Oh yeah, and Cameron Diaz.

There are others. That guy who directed The Getaway. That singer with the warbly voice. His knowledge has yet to catch up to his enthusiasm. "I was once talking about Robert Shaw, who plays the shark catcher in Jaws, and I was saying how he's so underused these days, and then somebody told me he's been dead for fifteen years or something. Guess he's not doing much lately. Ha, ha!

As for heroes, there is only one. Billy Connolly. "I never laugh so much as when I watch his stuff. He's hysterical. He's angry, and he swears a lot. Nobody can swear like Billy Connolly. He swears so well. So properly. He packs opera halls on his own. He stands there for three hours on his own. I couldn't do it. It's easy to be witty and dry on radio or television interviews. But not for an hour and a half when there are thousands of people waiting for you to be witty and dry.

When it's suggested that anchoring a play is about the same, McGregor shrugs. "I guess. But I don't have that kind of talent. I have confidence in my work. I don't want to say I'm talented, because that'll be above my head in quotes: 'I'm very talented and have a huge penis.' " He chuckles, then goes for the obvious gag. "Better than having a small penis. [Beat] And no talent."

George Lucas isn't worried. "Ewan's talent will win out over everything. He's got a great future. He will survive Star Wars." McGregor agrees. He knows that he is, like his grandmother, happier in motion. Reflection is ponderous, dull. Which is why when he's asked, "Is this what you expected your life to be like?" he doesn't hesitate, not even for a second, before saying, "Yeah. I never even for a moment considered it not working out."