You've got to hope that Laura Linney never gets famous famous. Too many Us Weekly covers or shout-outs on Access Hollywood would destroy the sway she has on the art house crowd, that delicate balance she traffics between dimpled familiarity and subterranean subversiveness. Indeed, the sure-footed pro needs but a sidelong glance, a crinkled smile -- thankfully she appears to be no friend of Botox -- to convey oodles of self-doubt or supreme self-entitlement.

Even when she's playing second fiddle, Linney takes sparsely written parts, and evokes. Witness her affecting portrayal of Sarah, the too-devoted sister in "Love Actually," the workaholic who lets romantic love pass her by. Or the Macbethian tones in "Mystic River," where she took a demure housewife and turned her into a harpy from Hades.

But with "p.s.," Linney's latest effort, she's got plenty of material with which to play: Louise is a 39-year-old admissions director at Columbia's graduate arts school, an unhappily single woman who once loved an artist and now judges artists, the gatekeeper with yea-or-nay power over a potential student's future.

At work, in her corner office, Louise stumbles upon an application bearing almost the same name (with an extra first initial) as that artist she once loved in high school, a bad-boy type who died in a car accident shortly after giving her the heave-ho for her buxom best friend, Missy (Marcia Gay Harden). Just the sight of his name is enough to send her into a swoon. In short time, she's conducting a personal interview -- in a plunging party dress -- with would-be grad student F. Scott (Topher Grace), a cocky young artist with soulful eyes, a man-boy who flits between bravado and vulnerability. Before you can shout "Bad career move!" she's dragged him back to her pad, for a wildly inappropriate bout of shagging.

"I have to say, Louise," he tells her, "I'm really digging your executive recruiting."

"I'm completely at your disposal," she tells him.

Indeed. It's an unlikely courtship, never mind the significant age difference. There's a greater obstacle separating them: "You're into abstracts," he says, "I'm more figurative."

It's a statement about the way Louise lives her life. F. Scott is in the here and now. She's in the then. Notwithstanding her new love, Louise is marooned in the past, mooning over her high school sweetie and maintaining a chaste "friendship" with her ex-husband (Gabriel Byrne). They have standing dates, stuck in that curious safe space that amicably split exes often inhabit: No one's going back to what was, but neither is completely willing to let go of what is to find out what could be. But Louise's old crutch is rather abruptly snatched from under her and she's completely wrecked.

And so she spins around and around, trying to figure out the mystery of F. Scott (yes, the name is an affectation). He paints like her old lover, feels like her old lover. Is he? As a plot device, it's a weak one. The film, the second from "Roger Dodger" director Dylan Kidd, never really answers the question. Rather, it introduces the idea, toys with it like a bored cat, and then bats it aside. At best, it serves as a metaphor for memory and loss, and the desire to take a loved one and make them over into one's preferred image.

Ultimately, "p.s." doesn't completely work: It's neither romantic comedy nor mournful meditation on lost love, nor a convincing hybrid. The script, adapted from a novel by Helen Schulman, ties itself into too many convoluted knots, particularly the one involving Missy, the duplicitous friend who never met a man of Louise's she didn't like. (Still, it's great fun watching Harden and Linney, reunited after "Mystic River," creating the savage cruelty that only longtime friends can inflict on each other.)

And yet, somehow, wondrous acting holds things together, particularly that of Linney and Grace, who's best known for his role in "Traffic" and television's "That '70s Show." Together they repel and attract each other, strung out by a fierce and dangerous chemistry that's thrilling to watch.

p.s. (105 minutes at Landmark's E Street Cinema) is rated R for profanity and sex scenes.

Columbia admissions director Louise (Laura Linney) starts a love affair with a grad school applicant who's eerily similar to a high school boyfriend who died in a car wreck.