"You're dead, bitch!" Such is the first line spoken—or, actually, screamed—in Shoot 'Em Up, and lest you have any doubts about what sort of movie it's gonna be, the rest of the opening scene should give you a pretty good idea. A quick list of what happens in the first few minutes: Clive Owen ravenously chomps down on a carrot; a pregnant woman frantically seeks a place to give birth; one car slams into another with jaw-clenching intensity; Paul Giamatti cheerfully recites a sinister limerick; Owen rants about how ponytails make men look stupid (he then handily shoots several stupid-looking men with ponytails); the aforementioned baby is delivered (with the help of Owen's handgun); maybe a thousand bullets shatter glass, concrete, and bone; and all of it's blasted out to the relentless drums and squealing guitars of Nirvana's "Breed." Goddamn. The point is this: Shoot 'Em Up is a blast, funny and clever and loud and fast. On its own, the film's opening sequence would be amazing enough; as an introduction to the gleefully violent Shoot 'Em Up as a whole, it heralds one of the craziest, funniest, and most badass action movies in recent memory.

"I just packed in all the things I would want to see in an action movie," writer/director Michael Davis enthusiastically tells me. "Packed" is the key word, as Shoot 'Em Up starts with a bang (or, more accurately, a whole lot of bangs) and doesn't let up until its end credits. The wireframe of a plot: Clive Owen is "Mr. Smith," and for a while, all we know is that (A) he likes carrots, and (B) he's got some lightning-fast trigger fingers. Sitting on a park bench one night, Smith's caught up in a gunfight involving the evil Hertz (a sneering, growling Giamatti); a few moments later, he emerges with a baby and a slew of firearms. As Smith teams up with a prostitute who caters to mommy fetishists (Monica Bellucci), Shoot 'Em Up evolves—or, if you're a snob, devolves—into an exhilarating, hilarious chain of bloody shootouts and Schwarzenegger-worthy wisecracks, borrowing liberally from John Woo, Quentin Tarantino, and Looney Tunes.

"The fact is, adventure movies are fun rides. They're popcorn movies, and you're inevitably going to smile, and you are supposed to laugh," Davis says, acknowledging what he calls Shoot 'Em Up's "unique tone." On one hand, the film takes its visceral, intricately imagined action seriously—but it also isn't afraid to throw in absurdist elements, like Hertz's task of having to check in with his nagging wife on his cell phone, even while he's on the job, doing his damnedest to kill and maim. Or we can look at it on another level: Our hero's name is Smith, and our villain's is Hertz. Something postmodern and witty and fun is going on here, even if Shoot 'Em Up is ultimately satisfied with exploiting adrenalin and spectacle, cinema's most base common denominators.

"I don't like action movies where they substitute chaos and mayhem for action," Davis says. "Where, say, a building explodes, or a building crumbles, and everything's falling and people are screaming or whatever. I don't find that exciting. I like to be with the hero in the heroic moment: 'He's in trouble. How does he take these guys down?' To me, that's the fun part."

Aside from an R-rated cartoon for grownups, probably the most accurate way to describe Shoot 'Em Up is as a series of "fun parts"—with scene after scene of Owen's charming, kickass Smith jumping out of the frying pan, into the fire, and back again, always to the increasingly volatile fury of Giamatti's Hertz. The shootout involving an oil slick is great; the one involving a head-on car crash is better; and by the time the skydiving gunfight begins—yeah, that's right—any hesitation one might have about just having a total blast is as forgotten as Davis' sense of realism. "If you're going to see a wish-fulfillment movie," Davis asks, "rather than conforming to reality, why not make a movie reality that's just fun to see?"