A star in both official languages, Montreal actress easily jumps between French and English films, though it takes her a moment to adjust to the different demands.

Caroline Dhavernas is a poster girl for official bilingualism. The Montreal actress will next be seen on the big screen opposite Paul Gross in the Canadian actor/director's First World War drama Passchendaele.

In the flick, which opens here Friday, Dhavernas plays a nurse in a Calgary hospital in 1917 who takes care of an ailing Canadian soldier, played by Gross, and, as is always the case with her English performances, there isn't even the slightest trace of a franco Québécois accent in her delivery.

Dhavernas is, in fact, a francophone - something the English-language producers with whom she works often don't even realize because she's so fluent in the language of Anne Hathaway.

She loves being able to work in both languages, effortlessly shifting from American films like Hollywoodland to English-Canadian projects like Surviving My Mother to French Quebec films like the recently wrapped comedy De père en flic. That one stars Michel Côté and motormouth comic-turned-thespian Louis-José Houde as father-and-son cops, and it is expected to be one of the major local film releases next summer.

In an interview this week in a spacious suite on the 19th floor of the Queen Elizabeth Hotel, Dhavernas said toiling in each language is really quite a different experience.

"It's always wonderful to shoot here (in French) because it's my language," said Dhavernas. "So it'll always be easier somehow because I own the words, much more than I do in English. But it's an interesting phenomenon. When I work in English there is some kind of distance between me and the words, and that's very comfortable to work with. It's a difficult thing to explain. I like it. And when I go back to working in French, it always takes me a few moments to adjust. It's like I don't have any control over the words for some reason. I've heard Antonio Banderas talk about this on television once, so I know I'm not crazy and I know I'm not the only one."

For those looking for the secret formula to become as happily bilingual as Dhavernas, here's how her parents ñ actor Sébastien Dhavernas, who is running as the Liberal candidate in Outremont, and actress Michele Deslauriers ñ did it. They put their daughter in French school for kindergarten and grade one, then she moved over to elite English private school The Priory in Westmount for the rest of grade school, and, with that English base, the NDG native again hopped the linguistic fence, and did her high school years at Villa Maria en français.

"My father had done the same thing," said Dhavernas. "It's a great way of learning because you get to learn how to read and write in French (in kindergarten and grade one), which is important, and then you do it all over again the next year in English."

She also started spending a lot of time in New York City when she was in her early 20s and that's where she really perfected her English.

"You become kind of a sponge. At least that's what I do. I look at people, and hear the accents and the cultural differences."

That helped her enormously when she auditioned for and won the lead role in the quirky, critically-acclaimed Fox sitcom Wonderfalls, which, sadly, lasted a mere four episodes on the network back in 2004.

"English comedy has a very specific sense of humour and rhythm, and it's very different from French comedy. So I was like a little computer taking all this information in and trying to make it my own."

Passchendaele is, as the title suggests, a re-enactment of the World War I battle of the same name, but at the heart of the movie is a classic romantic drama about an unlikely couple. Gross's Sergeant Michael Dunne is smitten with Dhavernas's Sarah Mann from the moment he sets eyes on her in the Calgary hospital where he's recovering from his battle wounds, but there are no small amount of obstacles keeping these two apart. Sarah and her brother David are ostracized by the community because their dad fought with the Germans ñ and died - at Vimy Ridge, and that's left her emotionally wounded and reluctant to open up to anyone. She also happens to be addicted to morphine.

"The love story, to me, is very moving," said Dhavernas. "These two human beings are very damaged and meet under these horrible circumstances. She comes from a place where she's always been very responsible and she's promised to protect that heart of hers. Then when she meets him, something in her opens up and lets go. There's something so beautiful in that. In epic pictures, women are always very romantic. But I love the fact that she has an edge. She is very vulnerable but strong, and also with the morphine addiction and her background, all of that made her very rich and very interesting to play."

Since Passchendaele, Dhavernas has appeared in a couple of high-profile American projects. She shot Cry of the Owl, a thriller also starring Julia Stiles, and she worked on an episode of The Pacific, the World War II mini-series produced by Steven Spielberg and Tom Hanks. That drama, the follow-up to Band of Brothers, will be on HBO sometime next year.