If you're not familiar with doublesix's other work, "All Zombies Must Die!" looks kind of like a light-hearted version of "Dead Nation."

With drop-in/drop-out local co-op, fast-paced zombie-shooting action, a pervasive quirky zaniness and absolutely zero online modes, Doublesix’s upcoming “All Zombies Must Die!” is a game for anyone who’s ever lamented the death of same-couch co-op modes in modern video games. (You know who you are.) The game, which I got a peek at recently, is a downloadable, twin-stick shooter set for release this fall for PC, Xbox 360 and PlayStation 3. Doublesix, the small studio behind the game, previously made another zombie-oriented shoot-‘em-up, “Burn Zombie Burn!”

The first thing you’ll notice about “AZMD” is that it’s more “Shaun of the Dead” than “28 Days Later.” Cute, cartoonish visuals that reminded me a bit of Double Fine Productions’ “Costume Quest” are evident throughout, and most of the non-player characters you interact with have something clever or wise-assed to say.

The game supports up to four players, with one beginning the game as Jack, an avid video gamer who finds himself in the middle of a zombie apocalypse. Because Jack’s played his share of games like “Left 4 Dead,” “Dead Rising” and “Dead Island,” he quickly comes to the conclusion he’s living inside a video game. The other three primary characters are unlocked when Jack meets them through the course of the story, but mercifully Doublesix doesn’t require gamers to play through an introductory sequence before buddies can join in. Jack recruits somewhat generic-looking soldiers to fight at his side until he meets up with his ex-girlfriend Rachel, scientist Brian and alien Luxo.

The gameplay is that of an action role-playing game, with guns. Each character has four core statistics — attack, defense, health and speed — that can be leveled up, and which character you play as will determine which weapon you’re most proficient in, as well as special powers, crafting abilities and sidequests. The gunplay is pretty straightforward, twin-stick shooter stuff, while melee weapons are appropriate button mashy.

As you and your crew travel through the game, you’ll establish bases at various locations throughout the game world. Generally, you’ll want to set up shop near key strategic areas. Each part of the game world has its own loot drops and resources available for crafting and side quests. Torches, for example, require firewood and a lighter, so if you want to stock up on torches, you’ll quest in an appropriate map area and stock up on firewood.

When your tasked with clearing an area of zombies, the last few zombies you have to kill will become enraged, which is a highly technical term for "hard to kill."

Each of the four characters comes with his or her own side missions. Jack, for example, wants to prove to Rachel that they’re really part of a video game, while Brian seeks a scientific explanation for everything. Luxo the alien’s goal is simply to learn English, which he picks up from comic books and a DVD of “The Big Lebowski.” This leads to a fair amount of profane dialogue like, “Where is my f—in’ spaceship, dude?”

The bit of combat I got to sample in a brief hands-on session was overwhelming and intense. The game throws a lot of zombies at you, and ammunition is scarce. Despite its cute veneer, “All Zombies Must Die!” requires its four players to work together and to be careful in order to survive. (Friendly fire is turned on by default, but players can disable it.)

“AZMD” seems like the kind of cute co-op game I’d play with my wife if she were any sort of gamer, but the lack of online play means I’d likely end up playing solo. If you’re part of a gamer couple, gaming family or a household with gamer roommates, the downloadable game looks like it could be a fun diversion when it launches this fall.

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