Years before Zack Snyder became known for comic book adaptations like 300 and his DC Extended Universe movies, he made the transition from directing music videos to helming feature films with 2004's Dawn of the Dead, a remake of George A. Romero's classic 1978 zombie flick of the same name. Now, Snyder will return to the zombie genre with the upcoming Army of the Dead, an original action/horror flick he conceived for Warner Bros. in the late 2000s, only to rework the project for Netflix a decade later.

Netflix is already turning Army of the Dead into a franchise, having ordered both a live-action prequel movie and an anime-style spinoff series titled Army of the Dead: Lost Vegas. With the film's marketing underway ahead of its streaming premiere date in the spring, here's what you need to know about the plot, release date and trailer for Army of the Dead.

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What Army of the Dead Is About

Army of the Dead (2021) Cast

Directed by Snyder from a script he co-wrote with Joby Harold (King Arthur: Legend of the Sword) and Shay Hatten (John Wick: Chapter 3 - Parabellum), Army of the Dead follows a group of mercenaries who "take the ultimate gamble" by breaking into an abandoned Las Vegas casino after the city has been overrun by zombies and quarantined off from the rest of the world by a giant wall. Snyder has confirmed the film will reveal how the zombie plague started and where it came from in its opening scene, before diving into its heist storyline. The movie's backstory will then continue to be explored in the upcoming prequel film and anime series. "We really do a super deep dive on where this like zombie plague came from," Snyder said.

Why the Original Army of the Dead Didn't Happen

Dave Bautista and Zack Snyder on the Army of the Dead set

In its earlier iteration, Army of the Dead was set to be directed by Matthijs van Heijningen Jr. (2011's The Thing), with Snyder serving as co-writer and producer. When interviewed by io9 in 2011, Heijningen said the film "was really close to being made in 2008, but the [financial] crisis broke out, and then it was put on hold." Much like Netflix's Army of the Dead, the original version of the movie was envisioned as a big-budget tentpole and included some of the same plot points, most notably the U.S. government building a wall around Las Vegas to prevent the zombie pandemic from spreading beyond the city's borders.

Snyder later overhauled the film's story before pitching Army of the Dead to Netflix. Among the change he made was to drop the most disturbing element from the original script, which involved male zombies raping still-living women and giving rise to human/zombie hybrid offspring. Even without that vile plot thread, Army of the Dead is still a hard R-rated action/horror movie that includes "strong bloody violence" and "graphic nudity," in addition to more generalized zombie-related gore and mayhem.

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Army of the Dead Cast & Release Date

Wrestler-turned actor Dave Bautista (Guardians of the Galaxy) stars in Army of the Dead as the mercenaries' leader, Scott Ward, with Ella Purnell (Miss Peregrine's Home for Peculiar Children) playing his daughter, Kate. Other cast members include Garret Dillahunt (Fear the Walking Dead), Matthias Schweighöfer (You Are Wanted), Raúl Castillo (Atypical), Ana de la Reguera (Goliath), Omari Hardwick (Power) and Theo Rossi (Luke Cage). Tig Notaro will also appear in the film after replacing Chris D'Elia, who was cut in response to the actor's recent allegations of sexual misconduct.

Army of the Dead is scheduled to begin streaming on Netflix May 21. The film is part of the streaming giant's plan to release a new movie every week in 2021, as it continues to aggressively expand its library of exclusive movies and TV series. Army of the Dead will also follow on the heels of Snyder's R-rated, four-hour cut of Justice League, which is slated to stream on HBO Max starting March 18.

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Army of the Dead's Trailer

The Army of the Dead trailer offers a glimpse of Las Vegas post-zombie pandemic, with buildings in ruins and nary a living human in sight, save for Scott Ward and his fellow mercenaries. It also provides a sneak peek at the early days of the zombie apocalypse, with footage of the patrons at the slot machines in a Vegas casino suddenly being attacked and overwhelmed by hordes of the undead.

Directed by Zack Snyder, Army of the Dead stars Dave Bautista, Garret Dillahunt, Ella Purnell, Omari Hardwick, Raul Castillo, Tig Notaro, Theo Rossi and Ana de la Reguera. The film will release on Netflix May 21.

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