NO SOONER has 43-year-old Klavdia returned home from posting a lonely hearts ad than a respondent comes calling. He turns out to be an unsightly, bearded man in an old suit and hat who invites himself in and, almost immediately, asks if she's got any cash around the house.

From this opening, menacing first moment to its open-ended last, "Lonely Woman Seeks Life Companion" remains a special diamond in the rough, or given the low budget of this 1988 Soviet production, an uncut ruby.

By all accounts, the stranger, whose name is Valentin (Alexander Zbruyev), is completely objectionable. A drunk, a vagabond and a former circus performer, he simply won't leave Klavdia alone, even after she hits him on the back of the head. But it becomes increasingly clear to Klavdia (Irina Kupchenko) that Valentin, even though he's from a lower social class, has something to offer she can't find anywhere else.

Setting things mostly in Klavdia's modest, rather drab apartment and her less-than-radiantly lit hallway outside, screenwriter Viktor Merezhko and director Viacheslav Krishtofovich tell their story with understated straightforwardness. In the movie's relatively few forays beyond that apartment, they also provide an evocative feel for modern-day Russia -- a world of ugly tenements, socially claustrophobic offices and crowds lining up at liquor stores. From these unspectacular circumstances, a disarmingly simple, yet universal drama about human loneliness emerges, a sort of Soviet spin on Paddy Chayefsky's "Marty."

"Woman" would be nothing without the lead performance of Kupchenko (last seen in the Russian film "Forgotten Song for the Flute"). As Klavdia, a woman who's lonely but also hangs on to her pride, she's serenely on the mark without a moment of sentimentality. She builds to a cumulative triumph, as she contends not only with her own horror at Valentin's external circumstances but those of her class-conscious colleagues at the dress shop.

The movie's lightly adorned with comic touches. Valentin has an amusing, down-and-out friend called Kasian with whom he constantly scraps and makes up with. Klavdia's previously quiet doorbell now rings and rings with farcical regularity, as Valentin comes and goes or her neighbor comes in to report on a new love interest -- ironically, a man who initially came about Klavdia's ad. At another point, Klavdia is visited by three "Young Pioneers," who have also seen her ad and offer to peel her potatoes, scrub her floors and cheer her up as part of their good-deed obligations.

While it implies a "Frog Prince"-like parable ("I was a prince once," says Valentin at the beginning of the movie. "But I'm somewhat the worse for wear"), the movie mostly steers refreshingly clear of such cuteness. Although there are some princely qualities in Valentin, this is one love story where the frog pretty much stays a frog.

LONELY WOMAN SEEKS LIFE COMPANION (Unrated) -- Key. In Russian with subtitles.