Meet Sandrine Bonnaire, the accidental actress.At the age of 33, the elegant French beauty has appeared in some 20 films, many of them by the most prestigious Gallic directors.

She’s considered one of France’s finest actress, yet she never planned to make acting her career.

Back in 1983, it seems, Bonnaire’s sister Lydie, then 18, answered a casting call by one of France’s top filmmakers, Maurice Pialat.

“I went with her to support her,” Sandrine told Cine File during a visit to New York to promote her latest flick, the Oscar-nominated drama “East-West” (opening Friday).

“My sister was not good enough, but they chose me. But she was happy for me.”

So at the tender age of 15 Bonnaire made her screen debut, as a promiscious teen in “A Nous Amours.”

Her performance won her a Cesar (the French Oscar) as best newcomer. And a star was born.

Bonnaire doesn’t regret the way fate stepped in.

“I was very, very bad at school,” she said amid giggles. “That’s why I’m very glad to be an actress. Actors are the most lazy people in the world. That’s why acting is a good job. You work for two months and then take time off. I haven’t worked for a year and a half. It’s great.”

Bonniare — who in person is more delicate and petitie than she appears on screen — lives in a Parisian suburb with her 6-year-old daughter, Jeanne.

The father is American actor William Hurt, who has made two movies with the actress.

Bonnaire became pregnant during the making of a film in which she portrays Joan of Arc (not one of her flicks with Hurt). Thus the child’s name.

“I decided that if it was a girl I’d name her Jeanne,” Bonnaire told us.

And if it was a boy?

“I don’t know. But I felt it would be a girl.”

“East-West,” directed by Oscar-winner Regis Wargnier (“Indochine”), focuses on the family of a Russian doctor living in France during World War II who decides to return to his homeland with his wife (Bonnaire) and son.

They soon regret their decision — they have to adapt to a new, grueling life or face execution as traitors.

Catherine Deneuve appears as a famous French actress who tries to help the family.

How was it working with Deneuve, who has a reputation as a prima donna?

“I really like her,” Bonnaire reported. “She’s strange, but she’s brave and very nice.”

A critic recently wrote this of Bonnaire: Her “greatest physical attribute is her walk, which is brisk and androgynously sexy — she’s the Gary Cooper of French actresses.”

Bonnaire said she appreciated the Cooper reference — “it was very funny.” But she doesn’t like being called androgynous. “I don’t think it’s a real compliment,” she said.

Short films usually get short shrift. The PS2000 Short Film Exhibition is trying to do something about that.

The fifth annual edition of the fest runs each Monday in April at 8 p.m. at Anthology Film Archives (Second Avenue and Second Street), with a diverse lineup of some 40 flicks due to unreel.

Among the entries is the New York debut of “Men Make Women Crazy Theory,” directed by Zoe Cassavetes (John’s daughter) and featuring Alexia Landau, Ione Skye and Donovan Leitch. Screening tomorrow, it’s described as “a comic valentine to the neurotic lover in all of us.”

Tickets are free, although a $5 donation is “encouraged.” Information: (212) 505-5110.

V.A. Musetto is film editor of The Post. He canbe e-mailed at vam@nypost.com