What If... Zombies?!
"What If... Zombies?!" is the fifth episode of the first season of the American animated television series What If...?, based on the Marvel Comics series of the same name. It explores what would happen if the events of the Marvel Cinematic Universe films Ant-Man and the Wasp and Avengers: Infinity War occurred differently, with members of the Avengers becoming zombies and initiating a worldwide zombie apocalypse, while a group of survivors search for a cure. The episode was written by story editor Matthew Chauncey and directed by Bryan Andrews.
Jeffrey Wright narrates the series as the Watcher, with this episode also starring the voices of Mark Ruffalo, Chadwick Boseman, Paul Bettany, Sebastian Stan, Evangeline Lilly, Paul Rudd, Jon Favreau, Danai Gurira, Emily VanCamp, David Dastmalchian, Hudson Thames, and Tom Vaughan-Lawlor. The series began development by September 2018, with Andrews joining soon after, and many actors expected to reprise their roles from the MCU films. Animation for the episode was provided by Squeeze, with Stephan Franck serving as head of animation. The episode drew inspiration from the Marvel Zombies comic series.
"What If... Zombies?!" was released on Disney+ on September 8, 2021. The episode received mixed reviews from critics, with differing views on its tone, writing and story logic, and voice acting. A four-episode animated miniseries based on the reality of the episode, Marvel Zombies, was released on Disney+ in September 2025.
Plot
enters the Quantum Realm to retrieve his long-lost wife Janet van Dyne, but she has been infected with a quantum virus that has turned her into a zombie. She infects Pym before both return to his lab, attacking Scott Lang while their daughter, Hope van Dyne, escapes. Within 24 hours, the virus spreads across the Northwestern United States. The Avengers respond, but are infected themselves and turn the virus into a worldwide zombie apocalypse.Two weeks later, Bruce Banner is sent to Earth to warn humanity of Thanos' threat. Thanos' lieutenants Ebony Maw and Cull Obsidian arrive, only to be turned into zombies by a zombified Tony Stark, Stephen Strange, and Wong. Hope and the Cloak of Levitation kill the zombies, saving Banner. Another survivor, Peter Parker, brings Banner to meet the rest of their group—Bucky Barnes, Okoye, Sharon Carter, Kurt, and Happy Hogan. The group travels to Camp Lehigh in New Jersey, where they believe a cure for the virus is being developed, but are attacked by a zombified Steve Rogers, Clint Barton, and Sam Wilson, who infect Carter, Hogan, and Hope before the group kill the zombies in turn.
Before she succumbs to her infection, Hope sacrifices herself to bring the others to the camp, where they meet Vision, whose Mind Stone can reverse the virus's effects, exemplified by Lang's cured head being kept alive in a jar. However, the group also learns that Vision has been keeping a zombified Wanda Maximoff captive due to her resisting the Mind Stone and has been feeding other survivors to her, including T'Challa. Maximoff breaks free, kills Kurt, and infects Okoye while Vision, unwilling to live without Maximoff, sacrifices himself to give up the Mind Stone so the others can cure the world with it.
While Parker, Lang, T'Challa, and the Cloak escape in a quadjet, Banner also sacrifices himself to stay behind and turn into the Hulk to battle Maximoff and an oncoming zombie horde. In the hopes of broadcasting the Mind Stone's energy around the world, the survivors head to Wakanda, unaware that the country has been conquered by a zombified Thanos wielding a nearly-complete Infinity Gauntlet.
Production
Development
By September 2018, Marvel Studios was developing an animated anthology series based on the What If...? comic books, which would explore how the Marvel Cinematic Universe films would be altered if certain events occurred differently. Director Bryan Andrews met Marvel Studios executive Brad Winderbaum about the project as early as 2018, and his involvement was announced in August 2019. Andrews and Winderbaum executive produce alongside head writer A. C. Bradley, Kevin Feige, Louis D'Esposito, and Victoria Alonso. Story editor Matthew Chauncey wrote the fifth episode, titled "What If... Zombies?!", which features an alternate storyline of the 2018 films Ant-Man and the Wasp and Avengers: Infinity War. IGNs Tom Jorgensen said the episode title was a "jokey take" on the series' established naming convention, but was "also indicative of how much thought went into selling a zombie apocalypse that works in the MCU". This what if concept was chosen for the season over a Christmas-themed episode exploring what if the Avengers had shown up during the events of the MCU film Iron Man 3, told in the style of the film Love Actually vignettes; the Christmas-themed concept was ultimately used for the episode "What If... Happy Hogan Saved Christmas?" in the second season. "What If... Zombies?!" was released on Disney+ on September 8, 2021.Writing
In the episode's alternate storyline, Janet van Dyne returns from the Quantum Realm with a quantum virus that spreads throughout the worlds population creating a zombie apocalypse. The episode is a dark comedy horror adaptation of the Marvel Zombies comic series, with a number of direct references to the comics in the episode, more so than any other What If...? episode. Bradley had previously attempted to write a "dark body horror" story in which Peter Parker / Spider-Man turns into a real spider, taking inspiration from Franz Kafka's novella The Metamorphosis, which Marvel rejected for being too dark for their target PG-13/TV-14 audience. She then pitched the idea of MCU characters turning into zombies as an alternative story idea, not knowing about the existing Marvel Zombies series. Feige had previously expressed interest in a live-action Marvel Zombies adaptation in 2013, but was not able to accurately adapt the storyline to film due to the MCU's target demographic; he encouraged Bradley to pursue the idea in animated form for What If...?.Chauncey was the one to "spearhead" the episode, initially creating a draft with more gruesome deaths. He and Bradley were hesitant to have T'Challa / Black Panther appear without his leg because the racial implications of "a white couple
Casting
narrates the episode as the Watcher, with Marvel planning to have other characters in the series voiced by the actors who portrayed them in the MCU films. The episode stars the returning voices of Mark Ruffalo as Bruce Banner / Hulk, Chadwick Boseman as T'Challa / Black Panther, Paul Bettany as Vision, Sebastian Stan as Bucky Barnes / Winter Soldier, Evangeline Lilly as Hope van Dyne / Wasp, Paul Rudd as Scott Lang / Ant-Man, Jon Favreau as Harold "Happy" Hogan / Zombie Happy, Danai Gurira as Okoye, Emily VanCamp as Sharon Carter, David Dastmalchian as Kurt and Tom Vaughan-Lawlor as Ebony Maw.Tom Holland does not reprise his role as Peter Parker / Spider-Man from the film series, with Hudson Thames voicing the character in the episode; Winderbaum attributed Holland's recasting to possible conflicts with the deal for the character's film rights between The Walt Disney Company and Sony Pictures. Though Thames sounds similar to Holland, he created his own performance so he could identify with the character. The character was marketed as "Zombie Hunter Spider-Man". Josh Keaton reprises his role as Steve Rogers / Captain America from the first episode, in which he had replaced MCU star Chris Evans. Several characters appear in non-speaking roles, including Tony Stark / Iron Man, Dr. Stephen Strange, Wong, Cull Obsidian, Hank Pym, Janet van Dyne, Natasha Romanoff / Black Widow, Clint Barton / Hawkeye, Sam Wilson / Falcon, Wanda Maximoff, and Thanos; many of these characters appear as zombie versions of themselves.