Often cast as a man on the verge of a nervous breakdown, how does William H Macy keep his head above water in real life? Interview by Ariel Leve

Approaching the freeway in his racing-green Porsche, the movie star glances over his left shoulder to make sure the lane is clear. 'Ready?' he says, his foot hovering over the accelerator. 'Watch this.' Suddenly we are propelled forward as he floors it. We have accelerated from 0 to 60 in seconds. He smiles. 'Pretty cool, huh?' It is the perfect movie-star setting: top down, shades on, the Hollywood sign in the rear-view mirror. Everything about the moment is a stereotype, except for the actor who is driving. William H Macy.

The star of so many movies - including Magnolia, Fargo, and Boogie Nights - he is an anomaly: a movie star who has made it not on matinee-idol looks but on hard work. Sitting next to him, on our way to a voice-over test he has scheduled, it's tempting to think, for a heart-warming instant, that Hollywood is a meritocracy.

For every actor who has ever been faulted for doing too little, a thousand have been faulted for doing too much. Macy stands out. He is that rare thing in Hollywood - understated. 'I have humility, but in all candour I really do think I know how to act. Here's the thing about acting: at a certain point you have to say -This is as good as it gets.' Knowing when to say that is key.'

In his crumpled beige suede jacket and sensible shoes, he resembles a rugged creative-writing teacher at a liberal arts college. He carries a bulky black leather briefcase and an air that demands to be taken seriously. But he is also easy-going and laughs easily. There is nothing phony or pretentious about him. In person, he radiates subdued confidence - far from the lovable, and sometimes less compassionate, characters he often portrays on screen. What's more, he is well liked and hugely admired within his profession. Other actors revere him and want to work with him; he raises the stakes and their performance. 'If you're going to be one of the good guys in this business,' he says, shifting gears and gazing at highway signs, 'you have to make sure you do your job. Look, you can be the worst actress in the world, but if it's my job to fall in love with you I better fall in love with you. And if I don't, I better find it somewhere. That's the task - that's what they're paying you for.'

Just then it becomes clear we're lost. We exit the freeway and slow down. 'I spend so much of my time in this town lost. I don't know where we are right now. God damn it, now we're going to be late. Good thing we have a fast car.' We have landed somewhere in the San Fernando Valley and he hands me a map. 'Where in the name of God is Colfax?' he muses. 'Okay - Laurel Canyon - looking for Ventura - make a right - school zone - do you see Coldwater Canyon?' No. 'What about Magnolia?' I don't see it. 'Riverside?' Don't see it. He lets out a wry groan. 'We're in big trouble.' We pull into a service station; he unbuckles and runs inside. As it turns out, we're virtually around the corner from where we need to be.Once at the recording studio, he apologises for being late and gets right to work. Seconds later, reading glasses propped on his greyish sandy hair, he transforms into the vocal persona of an animated character - leader of the planet. Take after take, Macy effortlessly comes up with a different voice. Take 20: an imperious voice. Take 21: a high nasal voice. Take 22: a variation of the high nasal with a little bit of attitude. Take 24: stuffy nose. Take 25: patronising with stuffy nose. He is committed, professional and good-natured.

He wasn't always this content. When he first moved to Los Angeles in 1990 he was lonely. He didn't have a girlfriend and he was virtually starting over. He'd been an established stage actor on the East Coast; now here he was, starting out in films on the West, doing odd jobs, such as building sets, to supplement his income. It was new and tough. 'But it did get better when I started working,'he says. He needs to be busy. 'I find that I'm less moody as I've gotten older, but I do seem to get depressed on a regular basis - like every six months or so, it's inevitable that I hit the skids. I think it's some sort of a male lunar cycle. My wife is really smart, though; she's taught me the value of saying it's okay to be unhappy. Overall, I'm pretty upbeat.'

So what irritates him? 'Who said that they had to put a sticker on every single piece of fruit? And who decided that on television they can split the screen into four quadrates? Every single channel has a ticker tape now. Who decided that was a good idea?'

He admits to loving his life and feeling lucky. He is married to the actress Felicity Huffman - his second wife - and they have two small daughters, Sophia, almost three, and Georgia, who is now one. He gets up every day at 6am with Sophia and makes her breakfast. 'Oh, it's a great time with her,' he beams. 'She used to say, -I want my mommy!' so I used to say, -Well, your mommy's asleep.' Now when she says that, I say, -Tough. You got me.''

Back in the car, voice-over test finished, he has offered to drive me back to the hotel. One of the most salient qualities Macy has as an actor is his ability to humanise despairing, imperfect people. The characters he plays are often melancholy and strained to the limit, but Macy himself seems quite measured. 'You can abuse me for ever and I just eat it, and then all of a sudden I blow up and it's completely out of adjustment. You can be treating me like sh-- for months and then you do something inconsequential and I'll rip your head off. Sometimes it's years later.' Film sets are riddled with delicate egos and are breeding grounds for insecurity. It's often hard for actors to differentiate being 'difficult' and being 'assertive'. Macy's self-assurance comes from experience and the knowledge that he has the respect of his peers. He is now at a point in his career where he has what he refers to as 'juice'.

'I firmly believe that people have incredible radar. And if you know what your standards are, and they are inviolate, people just know what you will put up with and what you won't. So it's rare that I ever have difficulties on a set. I have a pretty good time.' But he is also pragmatic about an actor's place on set. 'We are pawns. It is not a collaborative business at all. It's a dictatorship - and, hopefully, a benign dictatorship. The director runs the set. The end. When actors start getting involved, you've got anarchy and it's the longest 12 hours you've ever spent in your life. I'm not a good yeller. If it happens, I'm sick about it for weeks afterwards.' When we met a few hours earlier at lunch, Macy showed up as a walking celebration of low-key stardom. He arrived at the table neither immediately accessible nor standoffish. On the cusp of guarded. There was a notable absence of attitude, no posturing - he is not cultivating an image. There are brilliant actors who go unrecognised and become broken down, bitter and angry. Had his breakthrough not happened, would he have kept at it? 'Hmm. I really don't know. I've given up acting a couple of times - nobody's ever believed me, they said, -Oh, Macy's giving up acting again' - but you know, I've always had a fire in my belly. I was always really aggressive with my career, I was very hungry, and I was really unhappy for a good amount of time. But I'll tell you, I had successes all the way along, enough to keep me in it.'

William H (for 'Hall') Macy was born in 1950 in Miami, Florida, though he lived in Georgia until he was 10, when the family moved to Maryland. His father was an insurance broker and ran a construction company; his mother, a 'southern belle'. He has one half-brother from his mother's previous marriage. Macy began acting in high school. He played Mordred in Camelot and also performed in a folk trio called the Minnesingers.He attended Goddard College in Vermont and majored in theatre; the playwright David Mamet was his teacher. He graduated in 1972, and shortly afterwards he, along with his college friend Steven Schacter and Mamet, moved to Chicago and founded the St Nicholas Theater, named for the patron saint of troubadours. 'We came out of the box in a full gallop,' Macy recalls. The first professional play he ever did was Mamet's American Buffalo, and it got both of them noticed.'For 10 years in Chicago, I was the [big] cheese.' Still, he was hungry for more.

The Goodman Theatre, Chicago's most reputable company, would cast all New York actors as its leads in every production; what was left over would go to the locals. It was same with movies that came into town to shoot. 'I chafed at the bit,' Macy recalls.In 1979 he moved to New York. It was rough. He was always able to get regular acting work, but augmented the pay cheques by tending bar and waiting on tables. He also taught acting - he'd done it since his Chicago days and enjoys it. He still teaches occasionally at the Atlantic Theater Company in New York, where he has been the director in residence since 2000. Asked if he would ever tell a student they aren't good, he says: 'No! I don't believe it's my place to do that.' He believes it's instinctive. 'So much of it can't be taught. The most obvious is comedy. If someone's not funny, you can put a gun to their head and you can't make them funny. I really believe that acting is mostly craft and anybody can learn it, whether you're any good or not - that's what you were born with. I work hard, I have a certain amount of talent, but I have a lot of craft and I work really hard at it.'

In 1987 he acted in his first film with Mamet: House of Games.They have since done four more films. Then came Macy's breakthrough. In 1996 he played the duplicitous car salesman Jerry Lundegaard in the Coen brothers' Fargo; it earned him an Oscar nomination for Best Supporting Actor. It was a tectonic career shift.

'One of the greatest moments was when I read Boogie Nights and I liked it a whole lot. The first script was so much racier than the shooting script, and I wanted to do it really badly. I met with Paul Anderson, the director, and I gathered my thoughts on how to get this role. Halfway through our meeting, I realised he was the one selling - I was the one buying. I thought, -Holy cow, this is great.''He followed the success of 1997's Boogie Nights with the role of the former quiz kid Donnie Smith in Anderson's Magnolia, which was released in 1999. It was his second film with Anderson. 'Paul's a great director. If he directed the phone book I'd do it.'

He is confident about acting and he attributes this to having had a kind of epiphany early on in his career. 'I woke up one morning and I was just tired of being afraid. It was a great global switch. I thought, -Okay, here's my life, I'm here in LA building sets, and the next time I get on stage I don't want to be afraid.' I got angry about it.

'One of the things about acting is, it requires you to take your attention off of one thing and put it on something else. It's really dangerous. When you're skiing, your natural tendency is to hug the mountain, but you've got to throw yourself down the mountain - get forward into your skis - otherwise you can't turn. And every cell in your body is saying, -You're going much too fast, it's too steep, get back on your skis and hug the ground.' It's the same thing with acting - it leaves you completely vulnerable. Plus you have anywhere from a hundred to a hundred million people watching; it feels life-threatening.'He says there have been times when he has questioned choices he has made. 'I chose the wrong movie, directed the moment wrong, acted the moment wrong, married the wrong person - I wish I'd done some stuff differently. I have regrets but I think you can't waste too much time on that. Past is the past. I kind of think the best way to live your life is do the small things correctly and trust in God.' Are you religious? 'Not traditionally religious, no. But I like to invoke God a lot. It sounds really cool.'

On the drive home, as we near the Hollywood Hills, he asks, casually: 'Want to see where I live?' Surrounded by orchards of peach, apple and nut trees, his home is a tranquil reward for all his hard work. It is a new house, built from the ground up, and they moved in a year ago. So did he build it himself? 'I write the cheques that make the whole world sing,' he replies.

It is spacious but not flashy at all - just lived in and placid, like Macy. There is a huge stone fireplace in the living room and a high vaulted ceiling. It feels like a softer, paler, lighter version of a lodge in upstate New York - a place one might go to for a weekend away to view the autumn foliage. Big leather armchairs and lots of wood.His children are just waking up from their naps, smiling and drinking apple juice from plastic cups. 'When it comes to lives, I won the lottery,' he says, scooping Sophia up. He didn't think he was going to have kids; he was in his late forties and says it was looking grim. But when he met Felicity, he knew instantly she was the one - although it took a while to get it together.

They finally did get it together six years ago - for the second time around. They'd been together for six years, then split. 'I had missed her every day for five years when we separated. I knew I was not happy without her. She always was one of my best friends ever and I was hot for her. I was ready, she wasn't, so I just kept pushing - until finally I said, -Listen, I'm gonna marry you. You really should get a dress. Because I know that's important to women. So get the goddamn dress because I'm gonna marry you.'

Outside in the back yard is Walter, the bernese mountain dog, who is also an actor. 'He did a movie, and afterwards we brought him back to the studio to record his bark. I'm not kidding. We needed a bark. He barks on command.' In front of us is the most extraordinary pool, which stretches flat to the edge of the hillside and stops. The sort of pool where it appears if you swim too far, you'll backstroke right off the mountain.

On weekends, Macy works in his favourite place, his woodshed above the garage, doing woodwork, turning bowls. It is filled with serious machinery. He presents, proudly, one bowl he has turned. This is his refuge. He works above the garage to unwind and relax, focusing on something he can control that produces functional items. It is the perfect antidote to the irrational world of an actor.

Back in the house, we get to the master bedroom; he points out his wife's walk-in closet and then the bathroom, the size of which still seems to impress him. 'Bet this is the size of your apartment,' he says, marvelling at his good fortune. As we talk, there is a palpable sense of contentment about him. He moves casually and explains what makes an actor courageous. 'The weird thing about acting is that you can't try harder. It gets worse when you try harder. The best example is on stage. You do a show that is just fabulous. You're spot-on and you know it. The cast is good, the audience eats it up. So the next night you go, -That was great, I'm going to do it even better.' Well, that's the kiss of death. The goal is to do it truthfully and simply and then stop. It's a challenge - to do just what is required, do it fully, and stop. Tony Hopkins is a great example. His moments are completely full. Not a lot of energy that you notice, but full. That's really hard.'

Upstairs, we step out onto the porch outside his office, where he and his writing partner, his friend from college days, Steven Schacter, do most of their work. They recently wrote Door to Door, which was nominated for a Writers Guild Award. Macy hopes to concentrate more on writing. Suddenly he becomes animated as he points towards the sky. 'Look: a red-tailed hawk. Isn't he a beauty? There he goes, whoa!' There's an owl that lives over here - he's the size of a Volkswagen. He used to take critters up on our roof and eat them - and he hoots.'

The moment has produced an almost sedating effect. Nature - and the luxury of access to it - seems an important part of his life: it gives him perspective. Clearly, he doesn't need chaos to thrive. He does not need to be a lunatic to produce. The acting is what is sacred - nearly religious - for Macy, and he flourishes in the imaginary environment but depends on reality - his home life - to keep him grounded.In the beginning, the proving himself, the hunger, was about making it. So now that he's achieved that, what drives him? 'It was about four years ago when I got the blues a bit and felt a little lost. Felicity said, -You've got to come up with new goals.' For so many actors the goal is to get a career, then,once you get a career, you've got to come up with new goals. That's when I started writing in earnest.And then kids came along, and they are overpowering in how much time they take. There comes a time when you say to yourself, -Okay, quit working towards a career, you have a career; you're a grown-up, you've arrived- unpack, you're not going anywhere.''

Now he can be picky. He can turn something down that comes easily and opt for something a little more challenging. He has the luxury of choice. 'I don't have the fire in my belly that I had in my twenties, but who does? I mean, I'm 50 and I got a family now. I have my standards, but do I do things for the money? Yes, absolutely; any actor who tells you he doesn't is just lying. I'm in this business to make a living. It ain't missionary work.'

He looks out over his property. The pool reflects the light of the setting sun.'Come on,' he says, 'I'll run you home.'He drives me back to the hotel and offers to talk more if I need to, but tells me he won't be around much. 'I'm leaving town tomorrow - getting an award at a film festival. I'm getting a... uh... uh... uh... I can't remember what it is. I'm a maverick - I know that.'