The dead have risen, and they're hungry. Consumed with a ravenous desire for human flesh, they are everywhere. All they do is kill, and the people they kill? Moments later, they get up and start killing themselves, infected with whatever it is that is causing the newly dead to rise. Society is crumbling. The world is going straight to hell. Your own family and friends may have joined the ranks of the undead. And they're coming right at you...
The Zombie Apocalypse is one of the enduring narratives of modern horror. Zombies have been around for centuries — the original "zombies" appear in Voudoun beliefs, and many "real" cases of zombiism have been attributed to the toxins used in Voudoun rituals - but the modern impression can be traced to the George A. Romero movie Night of the Living Dead (1968), which gave the world many of the original tropes which can be found in zombie apocalypse stories. It's a popular kind of story, so for some advice on how to do it well, you may find this page useful.
Be sure to check out Write a Story for basic advice that holds across all genres.
Necessary TropesYou'll need zombies, obviously. There are many different types out there; however, there's a few common details amongst them that you'll want to at least be aware of. They're often (but not always) slow-moving, generally move using the Zombie Gait, and lack any kind of intelligence or all but a few lingering remnants of their former personalities. They possess a ravenous, unending hunger for human flesh. (The Return of the Living Dead series was pretty much the only one to actually feature brain-eating zombies.) A bite from a zombie is both fatal and contagious — anyone who is bitten by a zombie dies soon after, only to be "reborn" as a zombie.
Zombie Apocalypse stories are also generally bleak, and feature the Downer Ending — often times, Anyone Can Die in a zombie apocalypse, and it's not uncommon for some zombie stories to end with everyone either dead or, even worse, having become a zombie themselves. Even if one or two people survive, then it's usually a bittersweet ending at best — the use of the word "apocalypse" in the description is a pretty good hint at what usually happens to the rest of the human race, whether or not the main characters survive here. It's often taken for granted that humanity is screwed when the dead rise.
Zombie Apocalypse stories also come with gore. Lots and lots of gore. People tend to get torn apart in these movies — quite literally.
What kind of zombie will you use? Although there's a few common tropes amongst them, there's a few different variants. Although both worked together on Night of the Living Dead, the zombies in the movies by George Romero and the movies by John Russo are in many ways quite different. Furthermore, the traditional "slow-moving" zombie has been gradually superseded in modern zombie movies by faster-paced zombies who run after their prey, at least initially, which is something you may wish to consider. Do you like the sudden, fast-paced horror of a horde of zombies chasing after the characters, or do you prefer the slow-but-inevitable style of the traditional kind?
You should also consider how the zombie apocalypse is started — is it The Virus? A Voodoo curse? A crashed, radioactive satellite (don't laugh — it's one of the reasons given in Night of the Living Dead)? God punishing the sinners on Earth? Hell being full? Whilst you should give this some thought for your own reference at least, it's not uncommon for Zombie Apocalypse stories to be vague about how it all started — no one knows how it started, it just did...
Also, how does zombiism spread? It's universal that a zombie bite turns you into a zombie, but some other works have additional means of transmission. In some cases, simply getting scratched by a zombie is enough to infect you. In Romero's films, everybody who dies turns into a zombie, whether or not they were bitten. This last one, more often than not, implies a supernatural/religious justification for the Zombie Apocalypse as opposed to a scientific one, so keep that in mind in case you want to use it.
Finally, how are zombies killed? Entire online debates have been held on the best way to accomplish this, so it's something that must be considered. Most zombie works have it so that the only way to permanently put down a zombie is by Removing the Head or Destroying the Brain. This applies more often than not with the traditional "undead" zombies. And the best part is that it also works on non-zombies too! However, more modern zombie rulebooks often have it so that the zombies are living humans infected with a virus, in which case anything that can kill a human being (blood loss, massive trauma) will kill one of these zombies as well. Other zombie works obey different rules (the Return of the Living Dead series has it that only fire will kill the zombies), so you can consider those too. Or, you can try coming up with your own and seeing how well they work.
A particular curiosity of zombie stories is that, although we all know what they are, no one ever seems to call them by name. You will rarely ever hear someone describe a zombie in a zombie story by using the word "zombie". This is something you may wish to consider as well.
Zombie movies are a popular form of horror movie for amateur and first-time filmmakers, as they're quite cheap to make — for the most basic ones, all you really need is a few extras made-up to look like corpses, a few props that could be improvised weapons, and a place to film in. However, this means that there's a lot of zombie movies. And not all of them are good. If you want to write a Zombie Apocalypse story, be aware that there's a lot out there, so you'll need to make yours stick out in some way. You will also need to make them good.
Another particular pitfall is that, due to a lapse by the filmmakers, Night Of The Living Dead is, in fact, in the public domain. This means that it's had wide exposure and has been remade, either in name or not, quite a lot. As such, many zombie movies tend to follow its basic plot — a bunch of people trapped in a house or other building, with the zombies trying to get in to eat them. This is very familiar — try to think of a new spin.
Possibly the largest challenge is dealing with the fact that a traditional Romero-style zombie is not much of a threat to a healthy human. They're slow and dumb. Since the key to any horror movie is peril, you need to find some way to either advantage the zombies or disadvantage the humans. You can: make the zombies faster, have the zombies mutate into more dangerous forms, have the zombies learn, add a lot more zombies, trap the zombies and humans together in tight quarters, injure one or more of the protagonists so they can't simply escape, introduce a character that the protagonists must defend, establish that the characters don't understand the rules (initially), or introduce dissent in the ranks of the survivors, either by introducing a power struggle among them or plain old psychological breakdowns. There are any number of ways to increase the danger. However, the biggest and most common pitfall of the genre is to balance the scales by making the survivors dumb. Since part of the appeal of the genre is the "What if this happened to you?" effect, making the characters act foolishly breaks the immersion of the audience.
Potential Subversions and Variations
What about a zombie apocalypse from the point of view of the zombie? That would certainly change the formula.
Suggested Themes and Aesops
Due to George Romero's influence, many zombie apocalypses done today have strong themes of social breakdown. Usually, we see social breakdown happen on a large scale first (i.e., the people we look to for help and protection are helpless, dead, unavailable, or have gone crazy in the commotion), and then on a small scale within the main cast. Stress makes people bicker and fight, and paranoia spreads. People have complicated love affairs. With no external society to check their actions, normal people may commit heinous acts. It is standard for several members of the core group to die — killed by zombies, or just as often killed by each other.
When this theme is prevalent in a work, it can't help but imply some statement about humanity — what we're really like when you take away our jobs, our homes, our internet communities. Under these conditions of stress, your characters can become heroes, monsters, something in between or who knows what else. Of course, if you're aware of this implication, you can just as easily subvert it.
Decay has long been a strong motif in zombie fiction, both physically and socially. It's just about mandatory, given the normal themes.
As mentioned above, most zombie movies, especially those made by amateur filmmakers with little money, tend to copy the plot of Night of the Living Dead, with the main characters trapped in some kind of building (traditionally a house, although we've seen shopping malls, military bases, pubs and many other variants) with zombies outside trying to get in. It's gotten to be more than a little cliche. How about inverting this — what if the zombies were trapped in a building trying to get out, and the main characters were trying to keep them in? Or what about a story where the main characters have to travel a long distance across zombie-infested territory, rather than being barricaded indoors somewhere?
Another idea would be to combine your zombie film with another genre. Shaun of the Dead cheerfully billed itself as "a Romantic Comedy with zombies," while Dance of the Dead crosses the zombie genre with the teen comedy.
Most zombie movies also feature a nakedly Downer Ending or, at least, a bittersweet one — it's generally assumed that the Zombie Apocalypse will become an apocalypse. This has been done so many times that, unless done particularly well, it can come off as being a bit cliché. Maybe you can find a happy ending? Perhaps the outbreak can be prevented, or contained to a small area, or even defeated?
Zombie movies are usually set in the present day — how about a period zombie movie? Or a futuristic one? Or one set on another planet?
Or maybe you could consider exactly when along the outbreak timeline the movie is set. Instead of focusing on the beginning, maybe you could start the story after the major outbreak where the main characters are living in a zombie-infested world. Or perhaps even further after that, where humanity has slowly started to rebuild itself but still has to be cautious of the remaining zombies repeating the cycle again.
Most of them are usually set in America as well. Why not try another country and deal with the unique problems, advantages, quirks and culture that comes with it? Perhaps you can pick a country with very little gun ownership, or has a harsh environment after civilization breaks down, or is densely populated on a small landmass, or don't know much about zombies because they haven't seen the movies? High School Of The Dead does just that, showing what happens when a bunch of Japanese high school students (and the school nurse, and later a little girl and a dog) find themselves forced to steal things (including guns) to survive, drive without licenses, and rely on themselves (and each other) rather than on government or authority figures, bringing in a whole bunch of Values Dissonance considering how Japanese culture works (also boobies).
You can also consider outside factors that will hugely complicate attempts to survive. What would happen if there was a major natural disaster during an outbreak, like massive flooding or an earthquake? What would happen if the outbreak started during a war or civil unrest? What if the military, domestic or foreign, started razing the entire country to kill the infection?
Also, consider what kind of people your plot will revolve around. Many zombie movies center on a rag-tag bunch of strangers who band together to survive, but there are many other people who have their own stories to tell. The common wisdom in zombie movies is to never go to the hospital because that's where the mass outbreak starts, but someone has to be there treating the sick, so why not focus on a group of doctors trying to deal with a mystery cannibalistic disease? Or the local police station, the people who are supposed to maintain order facing the impossible? Or a group of the elderly inside their nursing home? A bunch of kids stuck inside their schoolbus? A prison full of angsty inmates and scared wardens who now have to work together? The possibilities are endless.
Set Designer / Location ScoutAs noted above, the zombie movie is one of the cheapest kinds of movies to make; all you really need is a handful of main characters, a convincingly large 'army' of zombies, and somewhere — ideally somewhere remote and/or suitably apocalyptic looking — to shoot. So theoretically, a zombie movie can be set absolutely anywhere.
Props DepartmentFake blood. Lots of fake blood. Gallons, in fact. Also strips of meat, if you want to make the zombies tearing into some poor sod look very convincing. For internal organs, you can buy from suppliers (often the same ones that sell the fake blood), or make your own using guides found online.
Costume DesignerZombies tend to be dressed in everyday clothing that has been made very ragged. For further ironic value, some kind of uniform — police, medical, military — can be useful in showing what happened to the people who were supposed to deal with this kind of thing. Don't forget to throw in an Incongruously Dressed Zombie or two: films like this usually need a few visual gags to modulate the tension.
The clothes of the living tend to look little better, as they've been spending days, weeks or months running for their lives or locking themselves inside a building.
Casting DirectorYou will need lots of extras. Preferably extras who are very good at looking glazed-eyed, don't mind being dressed in rags and made up to look partially decomposed, and have a convincing zombie impression. There seems to be no shortage of volunteers; zombies appear to be one of the more popular roles that extras can get. For the actors playing the living, get people who aren't squeamish around violence and gore, can convincingly pull off light action sequences, and are willing to subject themselves to a brutal death scene (which is, after all, how many zombie movies end). The usual rules regarding acting talent and remembering one's lines also apply.
Stunt DepartmentZombie movies are frequently characterised by lots of gory shots of zombies either eviscerating some helpless and hapless bastards or themselves being eviscerated, shot and/or bludgeoned to death by the heroes, so you won't want to skimp on the fake blood. The opportunities for your characters — dead or living — to be dispatched is limited only by your imagination and budget.
Watch George Romero's original Living Dead Series trilogy — Night of the Living Dead (1968), Dawn of the Dead (1978), and Day of the Dead (1985). Most of the classic zombie tropes that people now take for granted, as well as the genre's association with social commentary, come from these movies. All three have been remade. Night, thanks to its public domain status, has had several remakes over the years, but the 1990 version starring Tony Todd and directed by Tom Savini is generally held up as the best of them, to the point where Romero himself has given it his stamp of approval (he produced and wrote the film). The 2004 remake of Dawn by Zack Snyder is also considered a good movie in its own right, albeit one with a very different, far more action-packed tone than the original. Romero's later Dead films (Land, Diary and Survival) are generally considered a mixed bag, but all three have their fans.
For an example of a zombie movie which takes the "classic" zombie formula and yet does something completely unexpected with it, watch Shaun of the Dead, a Romantic Comedy which is also a zombie movie (although often described as a parody, the zombies are actually treated entirely seriously for the most part; it's more a homage to Romero than anything). The two genres are put together and, amazingly, work incredibly well — it's both genuinely funny, genuinely sweet and genuinely frightening.
Don't forget to step into other mediums, too! First-Person Shooter Left 4 Dead and its sequel do it right: four survivors fighting off a horde of "infected" while trying to make it to the rescue chopper (or boat, or army truck, whatever). You're forced to work as a team, because otherwise the "special infected" will pick you off, and the amount of auditory immersion (I hear a spitter - watch your feet) is intense. And no, these zombies don't shamble their way around... which is a shame because if you're low on health, you do get along at a limp. Go check the game out (on YouTube, if nothing else) for an inside look at the Zombie Apocalypse in mutated virus form.
As long as we're on the subject of video games, Resident Evil (especially the earlier games) is also a must-play for anybody interested in zombies. Not only is it the Trope Codifier for the Survival Horror genre, it is also largely responsible for the resurgence of interest in zombie media in the late '90s and 2000s, as well as popularizing the idea of zombies being created by The Virus. Every game in the series (other than the Gun Survivor and Outbreak spin-offs) is available on PS3, be it on a disk or through the PlayStation Network, so if you own a PS3 you have no excuse not to play them. A word of caution: starting with RE4, the series started downplaying both the zombie and horror elements in favor of an action-shooter direction, with the "traditional" zombie enemies replaced with a cross between Invasion of the Body Snatchers and the "sprinters" of modern-day zombie fiction — a shift that wound up creating a Broken Base in the RE fandom. There also exists a live-action film series based on the games, but be warned: it is a classic case of divisiveness. A last mention would be the popular bonus game in Call of Duty: World at war. This "Nazi zombies" mode offers a survial-as-long-as-you-can spin on zombies in videogames. It supply's you with endless undead nazis that increase in numbers and speed each round. The gameplay is tense and addicting, and the atmosphere as well as the haunting shreaks of the 40's era zombies will stay with you. Give it a go if you think you can handle it.
The Epic Fails
Sadly, a fair chunk of zombie movies made since 1968 fall here. Don't ask about Plan 9 from Outer Space.
The Honourable Mentions
Although not strictly a zombie movie (in that its "zombies" are in fact living human beings who have been infected with a virus, and are not actually dead), 28 Days Later is an excellent horror movie which uses many of the tropes and themes common to Zombie Apocalypse stories and subverts many as well. Its success helped to spur on the recent popularity of zombie fiction. If you're going to use fast zombies, then 28 Days Later is a must-see for ideas on how to do it right (as is the aforementioned remake of Dawn).
Black Hawk Down, a war movie based on America's involvement in the Somali Civil War, has a lot in common with the zombie genre, and is often thought of as an honorary zombie film. The film revolves around a small group of soldiers surrounded by an enraged, riotous mob ready to fight tooth and nail. Literally thousands of Somali attackers are killed, and they just keep coming. Try watching it after playing Resident Evil 5.
For reading, check out The Zombie Survival Guide and World War Z by Max Brooks for great examples of zombie literature. The former presents a fairly effective set of "rules" for zombies, based largely on Romero's (with some modifications), that many zombie fans, books and movies have since taken as the "standard" for the genre, while the latter gives a uniquely international take on the Zombie Apocalypse.
The Walking Dead by Robert Kirkman is probably one of the best adaptations of a zombie apocalypse into serialized form. Starting out as a comic book series, it was later turned into a hit television series on AMC, which now uses it as one of their chief tentpole programs. Both feature a rich cast of characters, some memorable scumbags and villains (The Governor... brrrr), and loads of zombie mayhem, and are definitely worth a read or watch.