As high-spirited as its title suggests, "Wild Tales" opens on a savage note and ends, well, that’s for you to find out. In between its shocker start and equally startling windup, this Argentine anthology offers up a scabrous, often unsettlingly funny look at human behavior in extremis. It’s a mad, mad social Darwinian world, churning with men and women who, whether pushed a lot or just a little, are all eager to do the worst to one another. They pounce and then they pummel, engaging in drag-down fights that leave them black and blue and sometimes stone-cold dead.

‘Wild Tales’ Rated: R Opens Friday at Kahala 8

Comedy both leads and bleeds in "Wild Tales," which starts with a slinky number, Isabel (Marma Marull), roller-boarding onto a plane and into an unexpected reunion. It turns out that the unctuous guy across the aisle, Salgado (Dario Grandinetti), knows her former (never seen) boyfriend. A music critic, Salgado once sat in judgment of the boyfriend, to whom the critic had happily delivered a soul-crushing critique. An older woman seated nearby, overhearing their conversation, pipes in that she too — wouldn’t you know it? — was acquainted with the boyfriend and so it goes as one passenger after another echoes the same refrain. Just as each realizes that they know the same man, the plane banks and a queasy mix of dread and understanding begins ricochet-

ing from face to face and then …

Writer and director Damian Szifron hasn’t made it especially easy to write about "Wild Tales." All of its six distinct stories turn on someone’s overheated, sometimes murderous reaction to a grievance, real or perceived, major or absurdly minor. In the second story, "The Rats," a greasy-spoon waitress, Moza (Julieta Zylberberg), realizes that her only customer, Cuenca (Cisar Bordon), once did her family a profound injustice. Szifron sets the scene skillfully, starting with a dark and stormy night that inaugurates an equally foreboding initial exchange between waitress and customer. "Party of one?," Moza asks with a smile. "I see you’re good at math," Cuenca says, by way of hello. You don’t need to have worked in the service industry to feel the fury creeping into your heart.

Szifron is banking that his movie will stir up strong emotions, which at times makes "Wild Tales" feel like an experiment in human psychology, both his and yours. A few of the stories have a modest political undertow that, however sincere, largely exists to give the other characters permission to behave badly and you the go-ahead to laugh when they do. In "The Rats," Moza tells the diner cook (a peerless Rita Cortese) that Cuenca ruined her family and is now running for office. In response, the cook suggests that they poison him. And why not? Cuenca isn’t just a political menace, he’s also a bad customer — his fate is sealed. It’s no wonder that you snicker when the cook slams down some rat poison, her cheeks shaking and her eyes flashing conspiratorially with the edits and camera moves.

Szifron’s use of humor and steel-trap coincidence at times evokes O. Henry, if in a minor key. There’s nothing so stirring here as, say, in the O. Henry story "The Furnished Room" (1904), about a poor young man who rents a furnished room in which — after catching a whiff of his old lover’s perfume — he commits suicide, never knowing that she had done the exact same a week earlier in the very same room. Here, for O. Henry, coincidence is a means to an ending that’s haunted by the lives of its desperate, impoverished characters. Szifron creates inhabited worlds with comic timing and visual flair, but you can hear him chortling as he shovels his people into the grinder.

Not that you necessarily notice, at least not often. The best stories, like "Road to Hell" — a cautionary tale about untrammeled road rage — are so well executed (pun sort of intended) and as narratively stripped down as a Road Runner cartoon that they make worrying over ethics seem somehow self-indulgent. The cartoonish quality of Szifron’s violence has age-old appeal, of course, which is itself a moral to ponder. Notably, he is on shakier ground when he tries to complicate the stakes, as he does in "The Deal," about a wealthy family that pins a crime on a gardener who’s willing to take the fall for a price. He recovers nicely with "’Til Death Do Us Part," a brutally, gloriously streamlined story of love and jealousy that blows up a wedding, filling the screen with tumult and kisses.