Six years ago, Sarah Polley was flying home from Iceland when she first read Alice Munro's story about a woman who forgets she has a husband after a lifetime of marriage. Polley was 21 and freshly in love with the man she would marry. She had just finished shooting an odd little movie in Iceland called No Such Thing, co-starring with British screen legend Julie Christie. On the plane, as she read Munro's story in The New Yorker, she kept imagining Christie as Fiona, this woman with Alzheimer's disease who enters a retirement home, loses all memory of her mate and falls in love with a male resident. "I don't think I've ever been as affected by a short story," Polley recalls. "I was shell-shocked. I found it so moving and poignant and it went so deep in me. It just sat there for a couple of years before I did anything with it, this vision of a film that wouldn't go away."

Now 27, Polley is sitting in a café near her home in Toronto, sharing a pizza, and talking about how Munro's story, The Bear Came Over the Mountain, became Away From Her, a movie that she has written and directed starring Gordon Pinsent, Olympia Dukakis -- and Julie Christie. Dressed in a dark denim skirt and a low-cut white cotton blouse patterned with eyelets, the former child star looks thoroughly grown-up. But you have to wonder what drives a woman in her 20s to devote her feature directing debut to a story of old folks losing their grip.

Polley blames it on young love. "My fascination with those characters," she says, "came from the fact that I'm at the beginning of a relationship."(Three years ago, Polley married film editor David Wharnsby, 37.)"The idea of a long marriage became fascinating to me. What does love look like after reality has had its way with it, as opposed to those first obnoxiously passionate moments? What does it look like after decades -- after you've failed each other? That became so much more interesting to me than a traditional love story about people when they're young and dumb and boring."

Mature words. But then Away From Her(which has its gala premiere Sept. 11 at the 31st Toronto International Film Festival)is a remarkably mature and accomplished film. In fact, it's one of the most astonishing feature debuts by a Canadian director in ages. Whether it turns out to be a hit is anyone's guess. But there may be a niche at the multiplex for this kind of Bergmanesque romance -- a cool, northern answer to On Golden Pond, without the sentimental sludge. And given the right marketing push, with any luck it could even find a niche at the Oscars.

Our filmmakers have been struggling to adapt CanLit since before Polley was born, and largely failing. But at a time when English Canada's film industry is gasping for air -- a cinema in search of an audience -- Away From Her arrives like an oxygen tank. Polley's script transforms Munro's story with a fidelity that inspired the author to leave a glowing message on her answering service. And the movie strikes a rare alchemy. Though intelligent, artful and beautifully understated, it's warmly entertaining and accessible. Coaxing exquisite performances from actors old enough to be her grandparents, Polley has given a second wind to the careers of two Oscar-winning actresses, Dukakis, 75, and Christie, 65 -- not to mention Pinsent, a lion-in-winter who acts with heartbreaking restraint as he quietly shoulders the drama's emotional weight.

Pinsent, who felt blessed to be handed such a plum role at the age of 76, says Polley displayed relentless focus on the set. "Those of us who knew her as a young actress stood back and watched her with quiet amazement," he recalls, adding that she wasn't shy about reining in her elders. "I have a tendency to invent as I go along. And that didn't seem to be lauded. So I thought, 'I better mind my P's and Q's or I'll never get out of here.' " Pinsent says the young director won the confidence of her cast through an unswerving instinct for the truth of a scene. "She just can't be false, this girl. She really stuck to her guns."

Polley has always conveyed an unflinching honesty on camera. She's been in front of it since she was four, dodging fireballs in Terry Gilliam's The Adventures of Baron Munchausen and warming the hearth in CBC's Road to Avonlea. She came of age with devastating clarity in Atom Egoyan's The Sweet Hereafter(1997). And since then, she has charted a maverick course through two dozen movies -- some Canadian, some not, most of them adventurously independent.

While Away From Her is her first feature as a director, Polley has written and directed five short films. And she's spent more time on movie sets than many actors twice her age. But she's often expressed deep ambivalence about the profession, a serious actor wondering if acting was a serious way to spend her time. When I first interviewed her nine years ago, she dismissed her child star years as an exercise in exploitation: "You're in a really foolish, false world with completely screwed-up people. I don't know if it's any place for an adult, let alone a kid."

The Sweet Hereafter gave her a new respect for acting. Still, she wasn't sure she wanted to make a career out of it. She was more passionate about her left-wing activism, and she bridled against Hollywood attempts to tart her up. While she says her politics haven't softened, she's mellowed. "I don't freak out any more about what my image is. As you get older you realize those things don't define you. It's best to put your militancy into things that make a difference in the world, as opposed to whether or not someone says you were wearing Tommy Hilfiger and you weren't. It's like, who really gives a rat's ass?"

Directing, meanwhile, gave Polley a new appreciation for acting. "In a lot of ways," she says, "being an actor is the worst training you could possibly have for being a director. You've been in this environment your whole life, so you think you know it. But 90 per cent of everyone's job on a set, you soon find out, is to protect the actors from any pertinent information. It's not like you're being manipulative or secretive. But they have to go somewhere profound and do something quite emotional. You're not going to mention the weather is screwed and you have to condense three-day scenes into half a day and they better get it right or we're all going to hell."

Before the shoot, Polley turned to Egoyan for advice, and he says he stressed to her that "the actor is the only person who is doing something genuinely magical on set -- and that has to be protected at all costs." But Polley is such "an observant actor," he says she has a natural instinct for directing. "She has extraordinary antennae."

Now that she's seen filmmaking from the other side, Polley says, "I look at acting as this enormous privilege I never realized I had. It really is the dream job. As an actor, I slept at night. I don't sleep at night as a filmmaker." She wants to continue to do both, but adds, "I absolutely prefer filmmaking -- it's infinitely more fulfilling and exciting."

In casting Christie, Polley chose to work with someone who could be seen as an older, more eccentric version of her dissident self. The British actress, who shot to stardom in the 1960s with Darling and Doctor Zhivago, turned her back on Hollywood in the 1970s. Lapsing into semi-retirement, she threw herself into causes such as animal rights and honed a feminist critique of her own glamour. And for Polley, who worked with her on two films(No Such Thing, The Secret Life of Words), she's become something of a hero. "She has one of the most vibrant, curious minds I've known," says Polley. "She has too much integrity. And she has one of the more accurate bullshit meters I've ever experienced. Any piece of dialogue, a word that rang slightly false, we would talk about it."

While Polley developed her disdain for showbiz as a child star, Christie rebelled against the much larger role of being a Hollywood sex symbol. "That's pretty complicated for her," says Polley. "She's got this incredible analysis of that time and of herself. I don't think she has a lot of confidence in her ability as an actor. I think she thinks she would have been better at something else."

Although Polley may share some of Christie's ambivalence, by carving out a career as a filmmaker she can insulate herself against the perils of aging as an actress. But it hasn't been easy. In 2004, Polley's first feature script, Itchy, a dark drama about a child actor, was shelved after languishing for a year in development limbo -- a casuality of a new mandate at Telefilm rejecting auteur films to pursue commercial formula. Funding Away From Her, a $4.5-million production, was also an uphill battle. But it was championed by Telefilm's new chief, Wayne Clarkson, who has ushered in a more flexible mandate.

Polley prepared her shoot in meticulous detail, but the one thing she could not control was the weather. She wanted snow. With Christie's character striding into oblivion on cross-country skis, snow serves as the film's founding metaphor, a blank page of lost memory. But in southern Ontario, "there was no freakin' snow this winter," says Polley, who had to push locations further north to find it. She also had her heart set on classic songs by Neil Young, which proved elusive. But after protracted negotiations, her producers snagged the rights to Harvest Moon and Helpless. With Neil's voice drifting down a wintry ribbon of road, hockey playing on the TV in the retirement home, and reverential readings from Michael Ondaatje, this is a movie that feels gently yet indelibly Canadian.

An actress who once served as a poster girl for protest -- she had two baby teeth knocked out by a riot cop at 17 -- she now has to admit she's happy. "I have no complaints, which is not going to last forever," she says. "But it's really nice." And she gives a lot of the credit to her husband, who edited Away From Her. "I feel he's responsible for a lot of what I like about myself, which is fairly recently developed. He's such a listener and so doesn't need to be the centre of attention -- everything I'm not."

When they were first dating, Polley recalls, "I remember being really mad with him because he wasn't in love with me yet. I thought, if we weren't in love in three weeks, what was the point? And he said, 'Well, I have butterflies in my stomach, so I guess some people would call that being in love. But I look at my parents and they've been married for 45 years, and sometimes my mom's doing the dishes and my dad will come up and put his arms around her waist and kiss her on the neck. To me, that's what love is. It's endurance.' "

Before Polley gets up to leave, she lets slip that it's her third wedding anniversary. And here she is, spending dinner with a journalist, eating pizza. "It's terrible," she laughs. "But we've spent a lot of time together, sitting in a dark room editing a movie." Besides, it's early innings for romance. And Polley has her eye trained well beyond the horizon.

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