"Would you have me lose my heart? Would you have me lose my reason? Must I now give my life over to my feelings?"

The battle between love and reason rages on in the heart of Leonide, a princess desperate to restore the throne to its rightful heir in Marivaux's not-so-romantic comedy from 1732, "The Triumph of Love." As a plus, she also falls hard for Agis, the fallen prince, the first moment she sets eyes on him. But first she must go undercover as a boy and woo Agis' protector, the philosopher Hermocrate, not to mention his lonely sister Leontine. In the end, Leonide is not as sure of who she is and what she wants as she once thought. Marivaux sculpts the pain of love, its cruelty and anguish, as keenly as its glories.

This world premiere of a new adaptation by Lillian Groag, best known for "The Magic Fire," marks the first co-production between Cal Shakes and San Jose Repertory Theatre, the inaugural event in their new Bridging the Classics project. The theaters are banding together to share resources on the costumes and sets needed to stage the classics, such as this opulent 17th-century masterpiece. It's a triumph of love (and money).

"I believe that, as the major regional theater of the South Bay, it is our responsibility (and my desire) to provide our audiences with a balance of contemporary work and the classics," says San Jose Rep artistic director Timothy Near. "But classics are usually the most expensive to produce because of the big casts."

Pierre Carlet de Chamblain de Marivaux, the most often-performed playwright at the Comèdie Française (after Molière), was largely undiscovered in this country until the 1990s.

Writer-director Stephen Wadsworth, who scored a monster hit with "Triumph" at Berkeley Rep in 1994, sparked a renaissance of the playwright's work in America. San Jose Rep staged Marivaux's "Game of Love and Chance" in 1997. A musical version of "Triumph" hit Broadway the same year, before being mounted at TheatreWorks in 2000. The love affair with Marivaux peaked in 2001 with the movie version of "Triumph" starring Ben Kingsley and Mira Sorvino.

Now Cal Shakes and San Jose Rep are launching their own iteration of Marivaux's most popular work, but they say it's not about the vanity of staging a world premiere adaptation. They wanted to hear Marivaux channeled through Groag's sensibilities.

"All of what we know of Marivaux in this country has been through Stephen's eyes," says Jonathan Moscone, artistic director of Cal Shakes, where the play opens before its San Jose engagement. "As much as Stephen represented Marivaux, he also represented himself, his high-end romantic aesthetic, while Lillian brings a more bitter edge to it that is interesting to hear. Here we get to know Marivaux in a different way."

The Rep's Near echoes this sentiment. Having worked with Groag on numerous occasions, both artistic directors are certain the new production will spark new reactions to the text.

"Lillian is a very different director than Stephen," Near says. "Lillian's work is bold, passionate, earthy, wildly funny and of the people. She gets to the heart of the human behavior and what drives each character. Wait till you see the first moments of the play. What she has planned will immediately focus us on the `core' issues."

Groag, a theatrical gypsy who has directed everywhere from American Conservatory Theater and the Oregon Shakespeare Festival to the Shaw Festival in Canada, has made her name with a style that marries erudition with whimsy and gorgeously nuanced language with striking visuals that topple our preconceptions of the classics.

Moscone says, "She's so smart that she can play around with confidence. She's one of the most successful directors at marrying high and low art, comedy and drama. She loves a good fart joke as much as the intellectual discourse."

Groag, who studied in France, has long steeped herself in the European classical tradition, but had never before staged Marivaux. She adapted this play in a month, alongside her collaborator Frederick Kluck.

"I have a tendency to fall in love with the work I am rehearsing," Groag says. "It has been extraordinary to see how phenomenally psychologically accurate he can be, if you can say that about a pre-Freudian writer, how accurate he is about the politics of falling in love."

Falling in love may be easy, but staying in love - ah, that's the trick. Here the costs of love are as steep as its pleasures are deep. Happily ever after, it ain't.

"For Marivaux, it is a chilly process. It's not as romantic as we Americans want it to be," Groag says. "The role of power in relationships - it's not at all sentimental. People fall in and out of love with, shall we say, very upwardly mobile ambitions."

Subtlety is the coin of the realm in Marivaux. Beneath all the frilliness and finery lie uncertainty, doubt and pain. Indeed, the emotional tug of war between the lovers (Stacy Ross as the sly Leonide and Jud Williford as the lost Agis) makes a tart foil for the commedia escapades of the Harlequin and Dimas characters (played by veteran Bay Area clowns Danny Scheie and Ron Campbell).

"We don't have the same comfort with the mixture of comedy and seriousness here as in Europe," Groag notes. "Even in Shakespeare, right before Cleopatra takes the asp to her breast, there is a comic scene, a vaudeville scene. They didn't think anything about it. We are the ones who like to separate genres so much."

The bravery to mix it up, to mingle the delicious escapism of romance with the harsh reality of social expectation, is what marks the plays of Marivaux. If neoclassical theater often clung to form and structure at the expense of insights into the nature of individual character, Marivaux weds period charm with an almost postmodern sense of ambiguity. Put simply, in his canon, love hurts.

"He does not have a romantic bone in his body," she says. "Some of the cruelest stuff you've ever seen is in Marivaux, which we don't expect in a pretty and elegant Rococo universe, the world of Louis Quinze. Nobody expects it, but it's there, that cruelty."