Following up on 2007's much-venerated, sordid metaphysical puzzle box Timecrimes, director Nacho Vigalondo again cracks the genre box wide open in Extraterrestrial. 

Across all of Spain, 4-mile-wide flying saucers have appeared above the cities. But rather than allow the film to descend into an alien think piece or shoot-'em-up, Vigalondo uses the saucers as an excuse to empty the entire city of Madrid aside from a terrifically human, comedic love quadrangle in which everyone—including the poor, impotent viewer—is in helpless love with the same woman.

Julia (Michelle Jenner) is a fragile, wounded-eyed wonder, though she is less a fully fleshed character than a repository of affections, an achingly receptive pool of human sentiment. Julio (Julián Villagrán)—as the "other man" who wakes up from a post-coital blackout in Julia's apartment before the arrival of her dimwitted survivalist partner, Carlos (Raúl Cimas)—is a rumpled jolie laide of a man, his head clouded by thoughts of romantic possibility. Angel (Carlos Areces) is the obsessively creepy next-door neighbor, who remained in Madrid only because Julia did. 

What follows is not quite romantic comedy, and certainly not science fiction. In form it is perhaps closest to a loopy, farcical meta-play on the psychological thriller, as the group's claustrophobic situation and intense fixation on Julia become externalized as a hunt for the aliens among us. Each man, in turn, becomes the alien, but only as he becomes alienated from Julia. 

But all threat is blunted, made awkward and comic. The aliens, endlessly, merely hover. Empty buildings are blown up as largely symbolic gestures, guns remain unloaded except with tennis balls, and a massive, unopenable jar of peaches becomes the film's most dangerous weapon choice, if also an oddly suggestive metaphor. After all, these are lovers, not fighters.

Indeed, the whole damn film is a testament to rampant, ridiculous love gone wild in the old Spanish style, and to its absolute distortion of the world. Apparently, it takes a full-scale invasion to show that love makes you a stranger.

There are certain quibbles, of course, that in other films might have been fatal flaws. Both Carlos and Angel are broad-stroked cartoons, dim lights characterized by bold actions. Areces' Angel constantly carries the suspicious, startled expression of a fattened rodent in its last moments. Cimas' Carlos is an improbably good-natured jock who always desperately wants you on his side against imagined enemies.

But the heart of the movie remains the subtle interplay between Julio and Julia, in all their complicated, thwarted need for each other—and also in the ever-compounding, ever-slapstick pettiness of self-interest even amid worldwide disaster.

The alien invasion is no mere setup device, however. It is a necessary element in a film that otherwise might have been lighter than air. The situation's beautiful impossibility infuses the whole proceedings with the slow-dawning wonder characteristic of adolescent love. Whatever adolescence follows takes part in that wonder. Love, in the end, plays the role of the aliens.

Critic’s Grade: A-

SEE IT: Extraterrestrial screens at NW Film Center's Whitsell Auditorium. 7 pm Friday, 9 pm Saturday, July 27-28.