In "Illuminata," love is bustin' out all over. In fact, it's so choked with love that it hardly knows what to do with itself.

This explains its indulgences: It goes on too long and may be regarded as losing its way periodically (like the love-blinded). But it feels propelled by the heart's pure heat.

The love is made hotter by the fact that it's doubled. Two things are loved with equal fervor: A man loves a woman, and an artist loves his medium. For the sake of economy and clarity, the man is the artist and the woman is the medium. The artist happens to be the great actor John Turturro (who also directed, co-wrote and co-produced), and the medium happens to be theater, and the woman happens to be the great actress Katherine Borowitz, who in some poetic way represents its spirit. At the same time, she happens to be Turturro's wife in real life, too. That makes it pretty fancy: It's like Pirandello collaborating with Flo Ziegfeld on "Broadway Lullaby of 1903."

The setting is a small repertory company in New York at the turn of the century, so it's an invocation of theater before it went big biz and mass media. It calls up the now-vanished tradition of the theatrical power couple--Katherine Cornell and her husband Guthrie McClintic are the prime example--who produce, direct, star in and oversee the company; that was the pinnacle.

But whereas the real company run by Cornell and McClintic was beset only by the 18-year-old tyrant genius Orson Welles, poor Rachel (Borowitz) has her moony, writerly paramour Tuccio (Turturro) to contend with. And he's the least of it.

This is backstage drama as contact sport. It's a tribal celebration of that human subspecies known as theater folk, who, out of genius or fear or endless insecurity or for the sheer fun of it, give up their rational lives for a few minutes under greasepaint and in limelight. Plus, lots of sex and booze, and the freedom to be gay, straight or both, and escape from the tyranny of an alarm clock. They do seem to be, as someone has claimed, children of paradise, possibly even infants of paradise.

Turturro's Tuccio and Borowitz's Rachel fight all the battles of the theatrical and emotional life. With her support, he has a new play--fancily called "Illuminata," which illustrates their own internal lives and struggles with the meaning of love. The idea is to sell it not merely to the company but also to the theater owners--refugees from the stage themselves, played by Beverly D'Angelo and Donal McCann--and thereby elevate him to the level of other smart boys currently scribbling away, like Ibsen and Strindberg, those guys.

Meanwhile, all the children, the grown-up ones especially, are busily plotting and counterplotting on a variety of issues ranging from their careers all the way to their careers. It's a hot little crab pot of egos, and each ego is attached to a body, and each body has an id, so sex is mixed in with the whole bloody mess.

In fact, if a non-insider had done this film, it might be considered close to a hate crime: Turturro portrays his squirming, teeming performers as schemers only too willing to use sex as a means up the ladder. You could say this is immoral, disgusting, revolting, but it sure does look like fun. I guess it's a love crime.

Clearly the movie is intended to advance the lesser-known Borowitz into the public eye. In this, it succeeds ravishingly. She's one of those elegant beauties with a swan neck and alabaster skin and the carriage of a goddess who has an actual fondness for the human race. Botticelli would have painted her if he'd been around, but since he isn't, hubby makes do as best he can. And as earth mother and Zeitgeist, as well as plot fulcrum, she isn't overmatched.

Possibly he is. Turturro's own performance is far too grave and solemn for all the shenanigans; it's the movie's biggest defect. He's like a bad, puzzled Hamlet in the middle of "Hellzapoppin'." I suspect he meant his tone to be comic, yet he's so passionate an actor that he can't quite give it the distance of comedy. It feels too real.

The other treat almost worth the price of admission alone is a magnificent appearance by the Clown Prince of Geeks, Christopher Walken, as a ghastly critic named Bevalaqua who uses his power to procure male cast members for himself. Walken, who may not actually be from our solar system, much less our planet, is a passing strange apparition, long of leg and arm, pale of face, his line readings syncopated to a time-telling system as yet unknown to man, his odd body capable of sudden spurts of grace and equally sudden spurts of awkwardness. When he's paired with the great clown Bill Irwin and his mission is to seduce the unsure Irwin, the setting being an ornate apartment decorated in the theme of the male butt, the result is so odd that you don't know whether to laugh or gag. But you won't look away, I guarantee you.

You can feel the love of theater, too, in the names of the characters: In no other world could there be a Celimene, an Astergourd, a Dominique or an Old Flavio. There's even Pallenchio and a Beppo. Would that Turturro and his co-writer, Brandon Cole, had as much fun with the script as they did with the names.

Would that, furthermore, "Illuminata" were a plot gambit shorter, a tad more focused, and that Turturro didn't seem so stricken with his Wellesian range of responsibilities. Then it could have been extraordinary instead of merely unusual.

Illuminata (95 minutes, at Cineplex Odeon Inner Circle 3) is rated R for sexual activity and nudity.

CAPTION: Tuccio (John Turturro) is the playwright of a struggling New York repertory company and Rachel (Katherine Borowitz) is his muse in "Illuminata."