Warning! Minor spoilers for Army of the Dead below.
Army of the Dead has joined the ranks of popular zombie movies while paying homage to its successor Zombieland. In a blink-and-you'll-miss-it moment, the Netflix movie subtly references perhaps the most iconic line from Zombieland. The specific moment in Army of the Dead proves just how important Zombieland has become to the zombie genre as a whole.
The hit 2009 movie followed survivors of a global zombie outbreak. Early in Zombieland, Columbus (Jesse Eisenberg) and Tallahassee (Woody Harrelson) team up to better their chances of survival. Their opposite natures complement each other — Tallahassee is bold and reckless, whereas Columbus, with his list of zombie survival rules, is neurotic and calculated while living in their zombie-infested reality. One of the top items on that list is the double-tap, referring to the fact that it's wise to shoot a zombie in the head twice to ensure that it's really dead.
Army of the Dead strays quite a bit from the typical zombie movie plot. Instead of focusing on the outbreak, it's centered on a heist that happens to take place in the middle of a zombie outbreak. It brings together a disparate cast of characters in a high-tension situation. In doing so, the Netflix movie possibly repurposed the famous Zombieland rule by directing it at a living person instead of a zombie.
The Zack Snyder movie's possible reference to Zombieland comes in a moment of mistrust between two characters. Coyote says to Martin, "If you screw me... two between the eyes." When he responds asking why two bullets, she simply says, "The second one's just for fun." In one aspect, this was likely simply foreshadowing the fact that Martin eventually betrays the group, and Coyote is doing her best to intimidate him. But a zombie movie can't reference shooting someone twice without the viewer being reminded of Zombieland's double-tap rule. Army of the Dead makes sure to make the tribute its own, however. It was a fun way to reference the earlier zombie movie without evoking a reference that was too on-the-nose and would take the audience out of the story.
Zombieland reinvigorated the zombie genre for a new generation. Prior to its release, the vast majority of mainstream zombie movies were traditional horror films. While other zombie comedies came before it, Zombieland was one that broke open the genre, a wildly successful comedy that became cemented in the zeitgeist. The 2009 movie was so successful that it spawned a sequel about a decade later. But the way in which Army of the Dead flipped the script on the double-tap rule from Zombieland that's now ubiquitous in pop culture proves that the genre will continue to evolve into something beyond its traditional straight horror roots.