But Zombieland -- from delightfully outta-nowhere director Ruben Fleischer and screenwriters Rhett Reese and Paul Wernick -- is not a simple redo or ripoff or anything so unpleasant as to require such derogatory words. In fact, it’s pretty much only the fact that there’s zombies and there’s comedy that prompts the likening. Shaun was more sly and more poignant, in the end: Zombieland has no time for cunning or the gentler emotions when there’s the walking -- and frequently running -- undead to be dispatched posthaste, and with accompanying wisecracking (though some of that does ripple with surprising undercurrents of gentleness).

In fact, this outrageously violent and outrageously funny movie had me worrying about myself for a moment, that I’d finally succumbed to the peculiar sort of zombification that has afflicted our culture of late. We invented an entire subgenre of movies that allows putative heroic characters to kill with impunity -- to kill in nastily inventive and creative ways, and to kill and kill again -- while also supposedly allowing both the heroes and us to avoid feeling bad or guilty or ashamed or dehumanized by enjoying the killing, because those being killed are already dead. Shouldn’t we be disturbed by this? Doesn’t this mean we’re irredeemably fucked up? Won’t future sociologists look back on this as a symptom of the same psychosis that allowed us to wage an unbroken century of war?

And then I simply stopped worrying about it and went on laughing my ass off.

There’s none of that mucking about with the dawn of the dead here: Zombieland skips right over the reasons that hungry corpses are suddenly walking the land, skips right over the initial moments of the crisis (except for one very funny scene suggesting that some lonely guys might find themselves suddenly on the receiving end of some much desired female affection come the end of days), and dumps us into the long aftermath. How does one survive in Zombieland? Our unnamed protagonist, a sweet dweeb played by the charming Jesse Eisenberg (Adventureland, The Hunting Party), introduces us to his rules for survival -- I won’t ruin them for you, for our schooling in them makes up a largish chunk of the opening of the movie, and it’s a wonderful sendup of the clichés of zombie flicks. Suffice to say that Our Unlikely Hero has 31 rules when we meet him, and that events shall transpire that cause him to amend some of them.

While wandering lonely across the burnt-out highways of America, the sweet dweeb runs into an asskicking Twinkie lover (Woody Harrelson [Seven Pounds, Management], whose smirk has never more appropriate or more welcome), who refuses to give his name -- you don’t wanna get too close to people in Zombieland -- but invites Our Unlikely Hero to call him Tallahassee, after his destination; he dubs the sweet dweeb Columbus, after his. Soon, they’ve joined up with Wichita (Emma Stone: Ghosts of Girlfriends Past, The House Bunny) and Little Rock (Abigail Breslin: My Sister’s Keeper, Kit Kittredge: An American Girl), and they all keep their destination-names even though they decide to head somewhere else. They’ve all seen postapocalyptic movies, and they know to dismiss the rumors of a zombie-free paradise out West, or the one back East. But there’s another place that might be fun to strike out for...

If I have one big quibble with Zombieland, it’s this: A plot point turns on the theft of cars and guns from other nonzombie people, but why steal a car at the end of the world? Why steal guns? Isn’t everything you need just lying around free for the taking? Or is the up-close-and-personal of theft just a way to interact with another live person without the danger of getting too intimate in a positive way? It’s a minor quibble, really, and not much of problem, for the rest of the film is so despicably, so wonderfully amusing. If it’s not as sly as Shaun of the Dead, it’s still wily enough to let what could be its best visual joke slip by so quickly and so uncommented on that you might miss it, which makes the noticing of it that much more fun. (And it makes me wonder what other jokes I did, in fact miss.) And it plays up what could be its most shocking moment with exactly the right blend of impudence and absurdity and tragi-comedy that you’ll be marveling that Fleischer and Co. even conceived of it, never mind got away with it.

But they do. Cuz this is Zombieland, and all the rules are off. Except for those 31, of course.