Zombies are scary by virtue of their relentlessness and their ability to overwhelm and overrun almost anything, but there has always been great potential for comedy there as well.

Zombieland is not a parody of or a post-modern commentary on the zombie genre — like, say, Shaun of the Dead — but it is still a total blast. It’s a savagely funny comedy that makes us care for its characters quite a bit more than we thought we would.

The characters are all known by their hometowns, because who has time for real names when you could be eaten any second? Jesse Eisenberg plays Columbus, a variation on the deadpan nebbishes he’s played in other movies. It’s rather like his character from The Squid and the Whale were suddenly besieged by zombies. He may seem like an odd person to be a survivor of the zombie apocalypse, but his loner nature and preternaturally nervous disposition served him well on Z-Day. A world being ravaged by the shambling undead may be the only instance in which a lifestyle devoted to playing World of Warcraft in your apartment while eating Golden Grahams proves to be an adaptively beneficial trait. Columbus keeps himself alive by adhering to a set of rules (helpfully printed on the screen) that range from the obvious (do lots of cardio) to the should-be-obvious (beware of bathrooms).

Woody Harrelson plays Tallahasee, a redneck shitkicker who is obsessed with finding a box of Twinkies and gets a perhaps excessive joy from killing zombies.

Columbus soon meets Tallahassee (Woody Harrelson), a redneck shitkicker who is obsessed with finding a box of Twinkies and gets a perhaps excessive joy from killing zombies. The two team up because, why the hell not, and soon hook up with a sister act of small-time grifters, Wichita (Emma Stone) and Little Rock (Abigail Breslin). The four are all wary of each other, but they decide to travel together, heading west for a California amusement park that is rumored to be free of zombies. None of them particularly believes it, but it gives them something to do.

The film is the feature debut for director Ruben Fleischer, and was written by Rhett Reese and Paul Wernick, but the picture doesn’t show any obvious signs of being made by newbies, except perhaps for a general tone of exuberance and enthusiasm. The movie really just wants you to have a good time, and the filmmakers keep everything paced very well, with enough wickedly funny set pieces to keep the audience constantly engrossed.

The filmmakers also really seem to understand the wish-fulfillment aspect that comes with your standard zombie apocalypse –  the rules no longer apply, and you can do whatever you want, providing you don’t get eaten. We follow the characters as they treat everything they come across as their personal playthings, destroying convenience stores and camping out in movie stars’ homes in Beverly Hills (which results in one of the funniest and most unexpected sequences in any movie this year).

There are a few horror comedies, such as An American Werewolf in London, that manage to be both funny and scary, but Zombieland isn’t one of them. The movie concentrates mainly on being a comedy, with a little horror tossed in now and then. It has very few scares, but doesn’t skimp on the gore, mostly due to Tallahassee’s rather enthusiastic methods for zombie killing. He has a love of lawn tools matched perhaps only by Jason Voorhees.

The filmmakers understand the tropes of the genre, and give them a sly tweak every once in a while. Most zombie movies feature a bunch of people holed up and hiding from the world, but this is the zombie version of a road movie. And, of course, our heroes don’t much resemble the salt-of-the-earth characters we see in most films like this.

Zombie movies love to ladle on the metaphors, and Zombieland is no different. There is a difference between living and existing, after all, and the movie shows us how the characters come to differentiate themselves from the zombies as they stop thinking only of their own survival and forge emotional relationships with each other.

Of course, it helps that the relationships are pretty hilarious. Eisenberg doesn’t vary much from the fidgety deadpan he usually does (pair him with Michael Cera and you could have the driest buddy-cop movie ever made), but it’s really interesting to see that sort of character placed in a crazy situation like this.  He also has some terrific chemistry with Harrelson, and the scenes with the two of them bickering are a delight. This performance may be the best thing Harrelson has ever done. His combination of a relaxed drawl and razor-sharp delivery make his action-movie bravado absolutely hilarious, but as the movie progresses we come to realize that Tallahassee has more sweetness and pain in him that it seemed at first.

Stone was lovely and down-to-earth as Jonah Hill’s love interest in Superbad, and she provides a similarly smoky, no-bullshit presence here. And Breslin is maturing nicely as an actress. Her character may only be 12 years old, but she is easily as grown up as either of the men in the movie.

Zombieland is wickedly funny pretty much from stem to stern, but its greatest pleasures lie in letting its characters butt up against each other and discover how they complement one another as they form the closest thing they can find to a family. It’s rare to find a zombie movie in which the living people are the most interesting aspect.