"Desert Hearts," Donna Deitch's first feature, touches something about love that few movies even hint at -- not the tremulousness, or the hiding and jousting (although there is that), but the way the attraction of two lovers warps the world around them, throws it out of whack.

The fact that the two lovers are women hardly matters, although it does matter in the Nevada of 1959 where the film is set. Vivian (Helen Shaver), a professor of English, has come to Reno to get a divorce; to establish residence, she stays at the guest ranch of Frances (Audra Lindley). Brittle and skittish, Vivian stays aloof from the other guests, but she can't avoid Cay (Patricia Charbonneau), a high-spirited hellion who lives in a cottage out back.

For Cay, Vivian is the first woman she's met who can matter to her; for Vivian, Cay is the first woman, period -- she unlocks her sexuality. It takes awhile before they realize they're in love with each other; in fact, everyone else seems to realize it before they do. "Desert Hearts" is populated with men jealous of women and women jealous of women, but they're more than that, too -- they're not jealous, really, they're just outside.

There's a wonderful scene, for example, in which Cay, Vivian and one of Cay's casual lovers (Gwen Welles of "Nashville," who registers on the screen like a rocket) are sitting in the front seat of Cay's convertible, motoring along; the prop of the jealousy is the radio (Prokofiev versus rock 'n' roll), and the scene resolves with the three putting on sunglasses and staring straight ahead. Deitch shoots it straight-on, unedited, with a motionless, deadpan camera, and it's a hoot.

The movie is full of such gentle ironies, and Deitch lends it a confident pace that's leisurely without ever seeming aimless. Shaver is a regal presence, with swooping cheekbones and a rich, throaty voice; one indication of what's magnificent in her performance is the way she's able to show how something's lost, as well as gained, when Vivian finally (literally) lets down her hair. Falling in love with Cay might be a good move for her, but that doesn't make it easier.

And who couldn't watch Charbonneau for hours? She's plain gorgeous, with fiery onyx eyes and a creamy complexion (she looks like the Ivory Snow woman's tomboy kid sister). Charbonneau may miss on some of the details of her role (her accent, for example, is as peripatetic as a Greyhound bus), but she gets the essential thrust right -- her Cay is full of life, and she takes what she wants.

Altogether, "Desert Hearts" is expertly cast, and one of Deitch's subtle achievements is the way she's able to give a movie that focuses on two lovers the feel of an ensemble piece. Among others, Andra Akers (as a local country music queen), Anthony Ponzini (as her betrothed), James Staley (as Vivian's hick lawyer), and James Dean-pretty Alex McArthur (as Cay's half-brother Walter) all fill their space without exceeding it. At times, they make you think you're watching a Robert Altman or Alan Rudolph picture.

That's not to say there aren't problems with "Desert Hearts." The cinematography is generally fine, but erratic; and cinematographer Robert Elswit never figures out a way to make you feel the heat of the Nevada desert, though the characters complain about it. The screenplay (by Natalie Cooper) is pungent, but it can also be a bit literary. And Audra Lindley (late of "Three's Company") is crusty enough to choke on.

Deitch makes some questionable choices, too. The scenes are connected with slow wipes across the screen, which become distracting. And there is a long love scene, shot in tight closeup, which may be too explicit for the movie's tone, and is definitely too long. Still, this is an astonishingly polished and nuanced first film. It deserves to be celebrated, not quibbled with.

Desert Hearts, opening today at the Circle West End, is rated R, and contains nudity in sexual situations.