AT THE beginning of "On connait la chanson," also known as "Same Old Song," SS Officer Von Choltitz (Gotz Burger) gets a phone call -- direct from der Fuehrer -- to destroy Paris. He resists Adolf Hitler's order and Paris is saved.

But in Alain Resnais's marvelously playful movie, written by Agnes Jaoui and Jean-Pierre Bacri, the unspoken question is: Just what "Paris" did Von Choltitz think he was saving?

If he was protecting the city of lights and romance, as serenaded by the likes of Maurice Chevalier and Charles Aznavour, then Resnais has an ingeniously mischievous rejoinder.

But first, let me attempt to summarize the storyline. It's complicated. Odile Lalande (Sabine Azema) is an assured control freak, who ignores everyone's needs but her own. So she's unaware that her husband Claude (Pierre Arditi) wants to leave. And she has little patience for her tour guide-sister Camille (Agnes Jaoui), who is complaining of panic attacks, nausea and depression.

Meanwhile Simon (Andre Dussollier), a real estate agent, who writes radio plays on the side, falls for Camille after attending one of her tours. But unknown to Simon, Camille has already fallen for Marc (Lambert Wilson), who just happens to be Simon's obnoxious, cell phone-toting boss.

Marc, a sleazy sort, is also selling an apartment to Odile and Claude without telling them an enormous building is about to obscure their lovely view.

Confused? The point is, everyone's entangled in the same social web without even realizing it. Paris seems to be the capital of souring relationships, unrequited affection and pre-diagnosed depression. People are either trying to leave their partners, or chasing the wrong one, or suffering from acute blues. And in this movie, part musical, part relationship roulette, and most definitely a tribute to "The Singing Detective" creator Dennis Potter, the characters are likely at any minute to burst into song.

Well, they don't sing, exactly. Resnais, a veteran of French cinema, has been a lifelong fan of musicals. But he doesn't make the characters go into gymnastic song-and-dance routines. Instead, they lip-synch well-known French standards from Chevalier, Aznavour, Gilbert Becaud and a variety of pop oldsters and new-sters. And after mouthing a few lines of the song, they go right back into the conversation, as if nothing happened. Their listeners (just as likely to sing themselves at some other point) are equally unperturbed. The effect is odd, amusing and rather sweet.

The effect shares similarities with Jacques Demy's "The Umbrellas of Cherbourg," Potter's "Pennies From Heaven," or Woody Allen's "Everybody Says I Love You," in which music has an entirely different dimension. Instead of transporting you away from the scene, the music brings you closer. You're suddenly thrust into an almost philosophical mode about the artifice of musicals, but you're nonetheless entertained.

ON CONNAIT LA CHANSON (SAME OLD SONG) (Unrated, 120 minutes) -- In French with subtitles. Contains nothing objectionable. At the Cinema Arts Fairfax.