Among February's tiny movies, Eric Rohmer's misbegotten "Full Moon in Paris," an examination of sexual mores among the idle French, has got to be the tiniest -- a thumbnail sketch of a thumbnail.

The movie launches from the French maxim "He who has two women loses his soul; he who has two houses loses his mind." (Oh, those French!) A coquette, Louise (Pascale Ogier), moves out on her man, the suburbanite Re'mi (Tcheky Karyo); she still loves him, she says, but she needs "to stay up all night once in a while" (he's an early riser). So she sets up a pied-a -terre in Paris and starts partying.

What she really wants is to exercise her power over men, a desire that can't be satisfied by someone she's already conquered. Louise proceeds to torture Octave (Fabrice Luchini), a pretentious writer who pursues her doggedly, by refusing him the favors she grants Bastien (Christian Vadim), a pretentious musician who pursues her not at all.

Ogier is none too attractive -- she's downright scrawny, long-nosed and heavy-lidded, with a big mouth framing little, lizard-like teeth. Her Louise toils obscurely as an assistant to a designer, but fancies herself an artist, creating decorative lamps in her spare time. Her airs, and her failures, explain her sexual neurosis -- the attentions of men fill the gap between her fantasies and her drab reality. "The one thing I've missed is experiencing loneliness," she says, but the minute she's alone, she grabs the phone -- being alone is hell for her. By herself she's Louise; with men she's anything they imagine her to be.

Rohmer has an acute feel for these sorts of pitiful deceptions, for the petty airs of the pseudoisie. Ogier is masterfully frivolous -- all the while she manipulates men, she pretends she doesn't know what she's up to, or why. And Luchini gives a marvelous performance as Octave. First he stares at Louise, then his eyes become distant, unfocused (in a comic strip, he'd have X's there). In neither case, though, does he register anything -- the seduction, not the seduced, is the thing.

But if these people and their problems are so trivial, why make a movie about them? "A Full Moon in Paris" is Woody Allen's "Manhattan" with be'arnaise sauce, but without any of that movie's humor or cinematic virtuosity. It seems to have been made on the full moon -- it's vacuum-packed and virtually weightless.

"Full Moon in Paris," opening today at the K-B Janus, is rated R and contains nudity and sexual situations.