Period dramas, especially English period dramas, have always had the air of "Masterpiece Theater" about them.

Think of England any time before the swinging '60s and images of prim Jane Austen virgins sipping tea in ornate but cold sitting rooms jump immediately to mind. Austen, Shakespeare and the Bronte sisters are the authors whose works are burned in our minds as the epitome of English drama.

When these works are translated to film, the are invariably enjoyable but stiff. Usually to see pre-20th Century peoples acting even slightly ribald you have to go to France (a la "Dangerous Liaisons").

This is why "The Governess" is such a departure. A hotly passionate, adulterous romance set against the early days of photography in the mid-19th Century, the picture is more complex and intelligent than any other offering in the recent resurgence in period film popularity.

From its inception, this was the intention, says writer-director by Sandra Goldbacher.

"There are all kinds of interesting gaps in the literature of that period that we just don't know about," Goldbacher opined while visiting San Francisco last month. "I mean, I love the novels of Bronte sisters, but there are certain parts of the story that you just don't see."

A few years ago, Goldbacher set out to delve into those hidden parts. Tapping into her own ancestry, she started a fictional diary from the point of view of a young Jew in 19th Century England with the intention of eventually turning it into a screenplay.

"I'd never seen anything about Jews in this period, and I found it really interesting," Goldbacher said.

Why a diary? "I just thought it would be an interesting in to the character, to let the her take (me) over. I wanted to have that feeling of seeing things through her eyes."

The eventual result was "The Governess," a unique and engrossing movie starring Minnie Driver as a young Jewish woman posing as a gentile to find work in 1830s London. A proud, independent girl, she doesn't want to marry an old man to pay off her murdered father's debts, so she takes a job on the Isle of Skye caring for a rich experimenter's bratty daughter.

The film draws parallels between the fleeting nature of a heated affair Rosina (Driver) strikes up with her employer (Tom Wilkinson) and his experimentation in photography, specifically his obsessive search for a permanent method of fixing an image to paper.

A diminutive, ashen woman in her mid-30s, Goldbacher doesn't look the type to be the force behind a high-brow bodice-ripper (although, she says, "I've had a few disastrous love affairs"). Extremely soft-spoken, with a tight but amiable smile, she does, however, seem like she might have more than a passing interest in the sciences, which she uses as a springboard for the more torrid parts of the story.

"I've always been interested in that period before people could actually fix images," Goldbacher said of the photography angle. "These pioneers were just working in the dark in connection to the search for this process, and it seemed to tie in interestingly to the idea (of an affair).

"How you actually keep yourself going day to day, not knowing if what you're doing is a complete and utter waste of time, because you're staking your whole life on something that might not work."

Both Rosina and her lover know the affair is ultimately doomed, but they bury their doubts in a cloud of unabashed sensuality, and the chemistry between Driver and Wilkinson is crushing, lustful and exciting.

Wilkinson is a remarkably versatile actor who is virtually unrecognizable from role to role, and he was Goldbacher's first choice to play the photographer who eventually breaks Rosina's heart.

"I think Tom is very good at that having things simmering under the surface. He's not frightened by taking on any kind of persona. He doesn't have to always play a heroic good guy."

Most Americans know him only as the eldest dancer in "The Full Monty," although he also played the cantankerous father of Lord Alfred in "Wilde," and here appears sexy, more vibrant and much younger (about 45). He was Goldbacher's first choices for the part.

Driver was her first choice as well and Goldbacher felt lucky in signing before "Good Will Hunting" hit. "Really, Minnie was the only one I wanted for Rosina. When I was writing the first draft, I just hoped. I sent it to her and she sent a fax saying how much she liked it," in part because of Rosina's unique character -- a Victorian Jew with a wicked wit and mind for science and debate that, in this conservative age, goes largely ignored because of her sex.

The true flavor of the period was a large concern for Goldbacher, who went out of her way to add elements of accuracy that would never make the cut in your standard stuffy period pic, like the scene in which Rosina upchucks during a bumpy carriage ride.

"I think carriage journeys then were incredibly unsettling. They weren't lovely little trots in the country."

To emphasize the separation of the Jewish society from the gentiles during this time, she also employed warm, dark photography in the early scenes with Rosina's family -- "to give the impression that the Jewish people sort of lived in the labyrinth underneath the Christian world" -- and applied a lighter, cold, bleak look to her new island home. "We really wanted it to be different from the world she had known."

In general, Goldbacher wanted her film to look different from anything else it might get lumped in with under the guise of genre.

"I think too many period films are just kind of pretty for the sake of pretty. The cinematographer and I wanted the visual look to reflect what was happening to the character emotionally at the time."

Goldbacher grew up in London, the product of a mixed Jewish-Christian marriage, a background she drew on for some of her childhood tensions for the script. "In my secondary school there was a quota for the number of Jewish girls and we were treated as second class. It's unthinkable really."

When she was in college studying French, she started hanging around with the film society crowd and switched majors, graduating into a bread-and-butter job making documentaries for the BBC while creating her own short films. Although "The Governess" is her first feature, she has two more projects in the works -- a contemporary love story/dark comedy that follows to women from ages 14 to 35 and an adaptation of Emile Zola's 1880 novel "Nana," about a self-destructive courtesan.