Sex and the ciudad: the sexy Spanish comedy Km. 0 throws together a dozen or so strangers on a steamy night in Madrid.

Km. 0 * Written and directed by Juan Luis Iborra and Yolanda Garcia Serrano * Starring Carlos Fuentes, Victor Ullate Jr., Merce Pons, Georges Corraface * TLA Releasing

Coincidence can be a tricky firing in the movies. "When it works it's delightful--after all, what are the odds that the one guy who can get Victor Laszlo and his wife out of Casablanca happens to be her ex? Or that four people in the same hotel in What's Up, Doc? would have the same plaid briefcase?

When coincidence becomes contrivance, however, that can be deadly. Just think of John Cusack and Kate Beckinsale frittering their way through Serendipity or of Paul Thomas Anderson's belabored prologue to Magnolia.

Happily, the new Spanish farce Km. 0 (named for the central starting point of Spain's roads, "kilometer zero" in Madrid) pulls off a delicate and hilarious balancing act, juggling 14 major characters (some gay, some not) and putting them all in exactly the fight (or wrong) place at the right time. It's a souffle you keep fearing will collapse, but the movie stays bright and entertaining all the way to its satisfying climax.

A hot August night brings a mix of people to the titular meeting point in the Puerta del Sol, and there the miscommunications begin. Young student Pedro (Carlos Fuentes) comes looking for his sister's friend Silvia (Merce Pons) but winds up going off with prostitute Tatiana (Elisa Matilla) by mistake. Tatiana's intended john, Sergio (Alberto San Juan), nervously goes for a drink with gay Maximo (Armando del Rio) instead. A smitten Benjamin (Miguel Garcia) pre Lends to be Bruno's (Victor Ullate Jr.) Internet hookup. And so on. The movie's small handful of locations and easily distinguishable three-act structure give the screenplay the feel of a stage farce, but the zippy pace and editing keeps the movie from feeling like a filmed play. (There seem to be almost no background extras in the film, but one of Km. 0's recurring jokes is the fact that practically everyone in Madrid leaves town during the dog days of summer.)

While the actual lovemaking remains off camera, sexuality permeates the film. From the characters' patina of perspiration caused by the late-summer heat (everyone complains about not having air-conditioning) to the steamy rendezvous (and near misses of sane), Km. 0 is the perfect summer date movie. Granted, it would have been nice to have a lesbian pair thrown in, but the movie does at least take an enlightened stand about sex workers. Rather than trot out the tired old rescue plot when young Pedro show's his concern over Tatiana--at least one disparaging comment in the film is aimed at Pretty Woman--he instead shows her how to dress better so she can charge more money. (The movie's male hustler, who services middle-aged women, lustily loves his job as well.)

Jaded gay audiences may question the notion of an Internet booty call leading to love at first sight, but in this movie's daffy atmosphere of romantic pixie dust, it plays convincingly. It also helps that they throw in a little naked flamenco dancing as a bonus. There's also the implication that all the film's characters are getting a little gay heavenly assistance, but, thankfully, this point isn't belabored.

One shudders to think of what contemporary Hollywood might have done with this same material, but these Spaniards get it just right.