Development , the creator and
head writer of
What If...? By September 2018,
Marvel Studios was developing several series for its parent company
Disney's streaming service,
Disney+; Marvel Studios President
Kevin Feige was set to take a "hands-on role" in each series' development, focusing on "handling" the actors who would be reprising their roles from
the Marvel Cinematic Universe (MCU) films. One of these was an animated series for Disney+ based on the
Marvel Comics run
What If...?, which entered development in 2018. The anthology series, which would be produced by Feige, would explore how the MCU would be altered if certain events had occurred differently, such as if
Loki wielded
Thor's hammer
Mjolnir. The hope was to have the actors who portray the characters in the MCU films voice them in the series as well.
A. C. Bradley was suggested as
head writer for the series by Marvel Studios executive Jonathan Schwartz after unsuccessfully
pitching as a writer for
Captain Marvel (2019). Bradley was eager to write a Marvel film due to her love for the franchise, and felt
What If...? was her opportunity to create many Marvel stories. Marvel Studios was impressed that some of Bradley's ideas for the series matched concepts they were planning for films, and she joined the project in October 2018. One of the concepts Marvel had devised that they asked Bradley to pitch on was what would happen if a 1980s Avengers team formed after a young Peter Quill came back to Earth; this concept would eventually be evolve into the
second season episode, "
What If... Peter Quill Attacked Earth's Mightiest Heroes?".
Bryan Andrews, a
storyboard artist on many of the major action sequences from the MCU films, met with
Brad Winderbaum—the Marvel Studios executive in charge of the series—about directing the series as early as 2018. Bradley and Andrews were officially announced in their roles in August 2019. In April 2019, Disney and Marvel officially announced the series. Marvel Studios had discussed adapting the
What If...? comics in the past, but decided not to do so until after the conclusion of the
Infinity Saga so they would have enough storylines to create alternate options of. Making the series animated allowed the studio to explore all of these ideas "unbounded". Winderbaum said it was not a coincidence that the series was set for release so soon after the
first-season finale of
Loki, which introduced the multiverse, since
What If...? explores facets of the multiverse in a way that Winderbaum believed made the series as important as any other MCU property; Bradley confirmed that all episodes of the series are canon to the MCU multiverse, with most of the episodes taking place in their own universe. The creative team of
What If...? met with
Loki executive producers
Stephen Broussard and
Kevin R. Wright as well as
WandaVision (2021) co-executive producer
Mary Livanos to establish a "rule book" regarding the multiverse, its branch timelines, and nexus events. The episodes are approximately 30 minutes in length, though Marvel Studios had originally told Bradley and Andrews to aim for 35 to 40-minute episodes; early production issues for the series resulted in the reduced run time. In December 2019, Feige revealed that the
first season would consist of 10 episodes, and that work had already begun on a second 10-episode season. However, because of the production delays caused by the
COVID-19 pandemic, an episode of the first season was not completed in time and was moved to the second season, bringing the first season to nine episodes; the second season was also reduced to nine episodes. Work on a
third season began by July 2022, when Bradley revealed that the second season was her final project with Marvel Studios. Story editor
Matthew Chauncey takes over as head writer for the third season, which was announced in August 2024 to be the series' last, and consists of eight episodes. A
Red Guardian-centered episode written by Bradley that was intended for the second season was released in the third.
Stephan Franck joined Andrews as director for the second and third seasons. In November 2024, Winderbaum explained that the series was ending due to "bigger [MCU] reasons" that were being determined in real time as different projects were released within
the Multiverse Saga. He said it was the right time for the series to conclude "from a story perspective", but did not rule out reviving it in the future. Executive producers for the series include Winderbaum, Feige,
Louis D'Esposito,
Victoria Alonso, Andrews, Bradley, and
Dana Vasquez-Eberhardt, with Carrie Wassenaar, Danielle Costa, and Alex Scharf producing. In July 2021, ahead of the release of
What If...?, Alonso noted that Marvel Studios was creating an "animation branch and mini studio", known as
Marvel Studios Animation, to focus on more animated content beyond
What If...?. During Marvel Studios Animation's panel at the 2022 San Diego Comic-Con,
What If...? and the other projects discussed were introduced as being part of the "Marvel Animated Multiverse".
Writing stars as the
Watcher, who narrates each episode of
What If...? Feige explained with the series' announcement that it would take "pivotal moments" from throughout the MCU and change them. Winderbaum felt it was "creatively healthy" to think of
What If...? as its own parallel world that "lives and breathes on its own terms" and did not need to have exact adaptions from the main MCU or comics. He added that it was liberating to work within the multiverse concept because the series could take greater risks or opportunities that other MCU projects are not afforded when they are concerned with connecting to future properties. Alonso said the series was an opportunity to introduce more diversity to the MCU and take advantage of more of the 6,000 characters that Marvel Studios had access to. Marvel Comics characters who have yet to appear in the MCU are not introduced in the series, but the writers considered creating new characters if it helped the story. For example,
Sam Wilson / Captain America could not be included in the first two seasons because the scripts were written before
The Falcon and the Winter Soldier (2021) had aired, with Bradley noting it "makes sense, you let the character live in live-action first and then go play in the multiverse"; Wilson's Captain America later appeared in the third season. Regarding new characters, this was first done in the second season with the introduction of
Kahhori, a young
Mohawk woman in an alternate timeline who seeks to discover her new-found powers after the
Tesseract crash-lands in the
Haudenosaunee Confederacy in
pre-colonial America where
European colonization has not occurred. Writing for the first season began in 2018, with the story arcs for the second season conceived during brainstorming sessions in 2019, ahead of writing for the season between January and October 2020. Each episode had an approximately 40-page script when first written. Because of the long-lead production for animation, there was not an opportunity for audience reactions to the first season to impact the creatives' work on the second season. Some of the initial 30 concepts that were not chosen for the first season also appear in future seasons. Episodes of the series were written by Bradley, Chauncey, and Ryan Little. Bradley stated that the first season was requested to highlight the "headliner" characters, such as Tony Stark, Black Panther, and Doctor Strange, as well as to only explore "what if" concepts for MCU stories from the
Infinity Saga; as such,
Phase Four characters do not appear until the second season, with Bradley and the writers also focusing more on the "scrappy", second string characters of the franchise such as Nebula, Darcy, and Hela. Andrews noted that following the first season, in which the "what if" concept were only small changes from what was established, further seasons were able to "expand out" beyond these small moments and "get a little bit wackier". As the writers were developing the initial scripts, they realized that
Captain Carter would "bubble up and became more important" alongside the
Watcher, and decided to revisit her story in each future season. Each episode and its alternate storyline is introduced and concluded by the Watcher, presenting it as "a cautionary tale in the spirit of
The Twilight Zone". The episode's tones vary, with some being darker or lighter than the MCU films that they play-off. Despite the series' anthology format, the writers conceived a story device for the first season that allowed them to have some connectivity between the episodes; this begins to be revealed in the first season's eighth episode before the finale in the ninth, which saw the formation of the
Guardians of the Multiverse, whose members were the various characters introduced in the preceding episodes. Along with Captain Carter, some of the storyline elements from the first season with
Doctor Strange Supreme and the Watcher are continued in the second season, with Strange Supreme becoming the villain of the season.
Casting Marvel's plan for the series was to have actors who portray characters in the MCU films reprise their roles in
What If...?, with more than 50 doing so in the first season. Feige revealed half of these actors at
San Diego Comic-Con in July 2019, along with
Jeffrey Wright being cast as the Watcher, who narrates the series. The additional actors reprising their roles for the first season were revealed in August 2021. Several characters in the series are voiced by different actors than those who portrayed them in MCU films. Winderbaum attributed some of the replacements to scheduling conflicts with the original actors, and explained that the creatives did not want the series to be "defined by the actors we thought we could get". When casting replacements, they looked to prioritize the performance for this series over an actor sounding the same as the original. Winderbaum felt the series' exploration of the multiverse gave a "cerebral justification" for the different actors. Over 30 actors reprise their MCU roles in the second season, with some of the different, recast voice actors reprising their roles from the first season. Over 35 actors reprise their MCU roles in the third season.
Animation for
Captain Carter. During the writing of the first season, Captain Carter emerged as a prominent character who would go on to appear in each subsequent season. The series features a
cel-shaded animation style with character likenesses based on the actors from the films. Ryan Meinerding, the head of visual development at Marvel Studios, developed the animation style for the series with Andrews. They considered using different styles for each episode, or basing the look on comic art by
Jack Kirby or
Steve Ditko, before settling on a single style inspired by classic American illustrators such as
J. C. Leyendecker,
Norman Rockwell,
Tom Lovell, and
Mead Schaeffer. Andrews felt this resulted in a "kind of heroic, hyper-realized, super-idealized look that feels iconic" while not being "pushed or cartoony", while Meinerding felt this was a unique approach to translating cinematic superheroes into animation that took advantage of the medium's stylization without losing the realistic, "monumental and powerful" feeling of the films. Disney's
Lady and the Tramp (1955) was also an influence due to its lack of "harsh line work" and because they felt it was "beautifully painted". Traditional 2D animation was considered but was abandoned when Marvel could not find studios who could handle the necessary work. Instead, the animation is "
2.5D", with 3D models rendered with 2D lighting to appear like flat drawings. Andrews enjoyed the opportunity to mix his knowledge of animation with the MCU, believing there was "an embarrassment of riches" in the storytelling they were able to achieve. Alonso said the medium of animation allowed Marvel Studios to work with new companies around the world.
Stephan Franck serves as head of animation on the first season. Scott Wright serves as animation supervisor for the majority of the second season, with Franck joining Wright on the fourth episode, and serving as sole supervisor on the fifth. Wright returned as the animation supervisor for the third season.
Flying Bark Productions and Stellar Creative Lab worked on all three seasons of the series, with Blue Spirit and Squeeze also working on the first season and SDFX Studios working on the second. The series'
opening title sequence was designed by
Perception, who sought to emphasize the series' themes by displaying "the beauty and idea of space". The sequence draws inspiration from the work of film poster artist
Bob Peak, particularly his artwork for
Star Trek: The Motion Picture (1979) and
Excalibur (1981), and uses imagery of glass shattering to symbolize the branching of the
Sacred Timeline.
Music By October 2020,
Laura Karpman was set to compose music for the series, which she called "the perfect composer playground" since she was able to reference existing MCU scores but also deviate from them. Karpman and the producers were inspired by
Alan Silvestri's approach to the
Avengers: Endgame (2019)
score for how to incorporate existing music from different MCU films. She explained that Silvestri weaved his own music into other composer's themes, and generally just touched on different elements from the existing music, so her approach for the series became "touch on [existing themes], then go on". Karpman had access to the sheet music and recordings of previous MCU scores but also adapted some elements by ear. For each episode, she looked at how the story aligned with the MCU, how it deviated from the MCU, and what the story itself required musically. When writing the series' main theme, Karpman knew that the opening sequence would feature images of shattered glass. She recorded the sound of shattering glass and manipulated it to create sound effects that were added to the theme. The main melody is played on a
French horn, with Karpman singing in the background as a reference to 1960s science fiction scores that featured female vocalists. Additional choir is also used in the main theme, singing phrases backward such as "what if", "Marvel", and "Stan Lee". Soundtrack albums for each episode of the first season, featuring Karpman's score, were released digitally by
Marvel Music and
Hollywood Records from August 13 through October 13. For the second season, Karpman was joined by her wife Nora Kroll-Rosenbaum. A five-track
EP for the third episode, "
What If... Happy Hogan Saved Christmas?", was released digitally on December 15, 2023. A soundtrack album for the season featuring selections of Karpman and Kroll-Rosenbaum's score was released digitally by Hollywood Records and Marvel Music on January 5, 2024. Karpman returned for the third season. == Release ==