Over the years Isabelle Adjani has become known for playing a succession of tragic feminist prototypes in historical films such as The Story of Adele H, Camille Claudel and The Brontë Sisters. It’s something of a surprise that Adjani’s latest role, in La Journée de la Jupe (Skirt Day), is a hassled French schoolteacher who is ridiculed for wanting to wear a skirt to work.

In the film, which received its premiere on Friday at the Berlin Film Festival, Adjani is still as magnetic a screen presence as ever, and for the first time she’s daring to perform without the least hint of glamour. Her character, Sonia Bergerac, is a pill-popping French teacher whose rumpled clothes and lank hair point to a life that has failed to live up to her high expectations.

All of this is placed in perspective when Adjani turns up to be interviewed at the bar of the Hotel Meurice on the rue de Rivoli. Wearing oversized dark glasses and a fur-trimmed coat wrapped around her shoulders, she makes the kind of hush-inducing entry only an actress of her stature can.

Many actors would have pooh-poohed the notion of starring in a tele-film, which is what Skirt Day was initially intended to be, but Adjani was enchanted by director Jean-Paul Lilienfeld’s script. The film’s good early reviews mean it will now be released in French cinemas at the end of March.

“What grabbed me about the film’s script was that it goes straight into a very extreme situation, there’s no introduction or preamble about life in the school,” says Adjani sipping a glass of Perrier (she rarely drinks and has never smoked). “As an actress I like this kind of challenge.”

It is Adjani’s first starring role in a film since Jean-Paul Rappeneau’s Bon Voyage over six years ago. The director François Truffaut once said of his Adele H star that she acted as though her life depended on it. I wonder if one of the reasons Adjani takes such a long time between roles is because she only chooses parts in which she feels she can fully immerse herself.

“It’s the first time anyone’s asked me that and I’m pleased because in France people can’t understand this type of thinking,” she replies. “Over here they love the kind of acting that is a bit distant, a bit cold. I’ve never felt like a French actress. If I don’t work very often it’s because what I read is written for formidable actresses, but actresses who make a habit of playing with their cup half full. I like films that rest in the memory so I try and choose parts which have some kind of social or emotional force. For me being an actress is not just a profession but a profession of faith.”

This almost holistic approach to acting has sometimes impinged on Adjani’s private life. She told one French magazine that it took her several years to get over playing the part of a possessed adulteress in director Andrzej Zulawski’s horror film, Possession. Even today, Adjani, who won her first of a record four Césars (France’s equivalent of an Oscar) for Possession, says she’d never take on a similar role.

“I try not to get too much into the mystical side of acting these days because I lived with an actor, Daniel Day-Lewis, who was, and still is, completely inhabited by his roles,” she says, offering a rare glimpse into her private life. “He’s an extraordinary actor but there’s nothing left over when he gives life to a character like the one in There Will Be Blood which is an amazing film. It’s a big sacrifice. It can cost you a lot.”

Adjani’s recent return to film acting at the age of 53 has coincided with a flurry of other high-profile projects. Lancel recently launched an Adjani handbag, while late last year she was the star of a lavish series of photos by French photographer Jean-Daniel Lorieux based on Mikhail Bulgakov’s novel The Master and Margarita . The €3m project, paid for by Russian businessman Yevgeny Yakovlev, has been shown in Paris and will travel to galleries in London and Moscow.

The common perception of Adjani in France is of an actress who lives in her own little world and is not rooted in reality. The popular stand-up comedian Florence Foresti has made a name for herself lampooning Adjani as a kind of Garboesque recluse who constantly says: “You know, I’m not mad.” This image of her couldn’t be further from the truth, says Lilienfeld, who directed Adjani for the first time in Skirt Day .

“She’s actually quite normal,” Lilienfeld stresses. “We chatted as parents, we have children who are about the same age and we spoke about their schooling and the difficulties they face. She’s quite shy and perhaps this shyness sometimes leaves people thinking she’s a bit aloof.”

When Adjani believes strongly enough in something she is not slow in coming forward. The daughter of an Algerian father who fought in the French army and a German mother, both of whom emigrated to France, Adjani was horrified when the French government proposed introducing DNA testing for the children of immigrants in 2007. The problem went away for a while when Adjani and a host of other personalities signed a petition criticising the idea. But the testing is now back on the agenda under Eric Besson, the new immigration minister.

“It’s quite ludicrous that France, which has always had a reputation as a country that has granted asylum rights to those who need them, should want to treat people in this way,” Adjani says.

After Skirt Day Adjani intends to star in another modern-day film which is being written and directed by her close friend Yamina Benguigui, the French-Algerian film-maker, a tragi-comedy in which Adjani plays a government minister with North African origins.

The new roles suggest that Adjani is hatching a plan to reframe her career as an actress on a contemporary footing, but she begs to differ: “I don’t calculate, if today I received three screenplays I liked for historical films I’d go and do them, without thinking perhaps people might get fed up seeing me in costume. I have several projects in the pipeline playing contemporary parts, but it’s really just a coincidence.”

Most of all Adjani wants to return to making “passion” projects like Camille Claudel (1988), in which she starred as the tragic sculptor who struggles to emerge from Rodin’s shadow. “That was a marvellous experience because it was a film the director Bruno Nuytten and I worked on like artisans,” she says. “We rented a small caretaker’s lodge and gave ourselves the time to really work through the film before making it.”

It doesn’t sound very French, I suggest.

“No, I know,” Adjani laughs. “It just goes to show I don’t live in the right country. I made a mistake ... the train came off the rails ... I do ask myself sometimes, what am I doing here?

The Berlin Film Festival runs until February 15. www.berlinale.de