Adventure Time: Fionna and Cake

• Madeleine Martin as Fionna Campbell, the gender-swapped version of Finn the Human.
• Roz Ryan as Cake the Cat, Fionna's pet cat who is the counterpart of Jake the Dog.
• Tom Kenny as Simon Petrikov, an antiquarian from the 20th century, formerly known as the Ice King.
• Andrew Rannells as Gary Prince, the gender-swapped human version of Princess Bubblegum.
• Donald Glover as Marshall Lee, the gender-swapped human version of Marceline the Vampire Queen.
• Sean Rohani as Prismo, a wish-granting deity residing in the Time Room and overseeing the multiverse.
• Kayleigh McKee as the Scarab, a multiversal auditor who hunts down Fionna and Cake.

• Pendleton Ward as Ellis P., the gender-swapped human version of Lumpy Space Princess.
• Cree Summer and Jinkx Monsoon as the Lemoncarbs, gender-swapped human version of Lemongrab.
• Vico Ortiz as Hunter and Fern.
• Audrey Bennett as Astrid, a young human girl and fan of Ice King's Fionna and Cake stories.
• Jeremy Shada as Finn the Human and Farmworld Finn.
• Hynden Walch as Princess Bubblegum, Candy Queen, and Bonnie.
• Olivia Olson as Marceline the Vampire Queen and The Star.
• Brian David Gilbert as the Winter King, an alternate-universe Ice King successfully controlling the crown's madness.
• Ron Perlman as The Lich, an ancient cosmic being as the manifestation of death.
• Felicia Day as Betty Grof, Simon's fiancée who disappeared after fusing with the malevolent entity, GOLB.

The characters "Fionna the Human" and "Cake the Cat" were created by Natasha Allegri

The idea for "Fionna the Human" and "Cake the Cat" evolved from drawings that Adventure Time character designer and storyboard revisionist Natasha Allegri had posted online during the show's earliest seasons.[6] Reception to the gender-swapped characters was so positive that the Adventure Time producers decided to write the characters into the series.[7] They debuted in Season 3's "Fionna and Cake", on which Allegri worked, and it functioned as both "a jab [and] a huge celebration of, [sic] the feeling of being a fan" and "allowing something completely ridiculous to make your heart tighten".[8] The characters would make additional appearances in Season 5's "Bad Little Boy", Season 6's "The Prince Who Wanted Everything", Season 8's "Five Short Tables", and Season 9's "Fionna and Cake and Fionna". In these episodes, Ice King shares stories about Fionna and Cake he made, who are in fact characters from modern shows; when he sleeps, a beam projects to his head to transport ideas of the fan-fiction.[4][9][10]

After the 2018 finale "Come Along with Me", a first spin-off series of Adventure Time: Distant Lands debuted in 2020;[11][12] before the latter's finale, HBO Max announced that a gender-swapped spin-off series was in production, on August 17, 2021, and ten half-hour episodes were planned.[13][14][15] In a 2022 interview, Jeremy Shada, the voice actor of Finn the Human, noted that he "may or may not be in that" when it came to the new spin-off.[16] In the Annecy International Animation Film Festival in 2022-23, Cartoon Network and HBO Max released sneak peek material,[17][18][19] while HBO Max was rebranded under the name Max as of May 2023.[20]

The Adventure Time: Fionna and Cake limited series was developed specifically with the young adult demographic in mind, according to Suzanna Makkos, an executive for both Max and Adult Swim: "The Adventure Time fans have grown up and people are still coming in the bottom, and they're aging up", she noted in an interview with Comic Book Resources. "[Fionna and Cake] felt like a perfect show for us. Tonally, it is very much Adventure Time, but Fiona's older. She's in the workforce. It's more adult, so I think it's going to bring in new fans, and it's also going to serve the fans that we already have."[21][22] In the United States, the limited series received a TV-14 certification based on the adult content (nudity, gore, profanity, and substance abuse); on the other hand, the series remains the TV-PG rating, just like Adventure Time, in Australia.[23][24]

Adam Muto, executive producer of Adventure Time, Distant Lands, and Fionna and Cake

Longtime Adventure Time and Distant Lands executive producer Adam Muto produced the limited series and also served as the showrunner.[25] In interviews with The Direct and The Washington Post, Muto and Ryann Shannon explained that the crew decided to focus on Fionna and Cake due to their popularity with the Adventure Time fandom.[26][27] Initially, Muto was concerned about working on another spin-off, given that sequels and reboots are often met with mixed success. To ensure that Fionna and Cake felt like its own production, the crew attempted to avoid "stepping on what [they had already] done before." The writers thus decided to ensure that the spin-off would be satisfying on its own and that it would focus on the characters' unique growth.[28] While Distant Lands is a limited series of four loosely connected vignettes, Fionna and Cake is more of an united story.[29]

When discussing how the production crew differentiated Fionna and Cake from the original Adventure Time series, Muto revealed that the crew members "were looking for ways to explore stories and characters that can be pretty different than Finn."[3] While Finn is a selfless and energetic hero, Fionna is more ordinary and realistic, since she does not live in a world of magic and is not as skilled as a fighter. In this limited series, therefore, the writers "wanted to see where [Fionna would] go if she kind of knew about that magical world from the first series which had been denied her".[3] Muto later added that the crew attempted to make Fionna more than just "Girl Finn" by giving her a unique personality that, in certain respects, is "way different than Finn and others."[26] The crew also took this contrasting approach when working on Cake: While Jake is a lazy dog with the power to stretch his body into a whole number of fantastic shapes, Cake lacks magic powers and begins the series as a regular house cat.[3] As to Jake's uncertain death, Muto decided to leave it ambiguous and noted that he does not want to "say definitively what the answer is". For adult Finn's possible future adventures, Muto liked the idea of Finn living his own life, and so they decided to not feature him in more than a few episodes. To make up for this, the writers brought back Farmworld Finn, a character who is different from the Finn of the main series.[30] Previously, while both the voice actors Olivia Olson and Erica Luttrell are of African descent, and Marceline's mother was a person of color, Marceline and Marshall share the look of gray vampire skin; in Fionna and Cake, Marshall Lee is with dark skin as a human character.[31]

The series makes a number of references to the 1982 sitcom Cheers. Muto explained that at first, references to the show were a joke, and that many of the crew members had never actually seen the production.[32] Initially, the song had been featured in the fifth-season Adventure Time episode "Simon & Marcy", wherein it was used by Simon as a way to retain his sanity.[33] In Fionna and Cake, the sitcom and its theme symbolize Simon's life before his discovery of the ice crown, and in Fionna's world, it is the only television program available, reflecting the fact that Simon is mentally stuck at that point in time.[32] The crew considered writing an episode that would take place in the world of The Marvelous Misadventures of Flapjack.[34] Although this idea was never fully realized, the series is briefly referenced in a scene in episode "Prismo the Wishmaster", wherein Prismo shows Fionna, Cake, and Simon a variety of universes.[35] The inspiration in animation often came from Seattle, where Muto was born, and a building was based on one from the University of Washington.[36]

Rebecca Sugar and Patrick McHale both returned to compose songs for Fionna and Cake

The three main characters were voiced by the original cast of Adventure Time, namely Madeleine Martin as Fionna, Roz Ryan as Cake, and Tom Kenny as Simon Petrikov. Donald Glover voiced Marshall Lee, while other cast members include Andrew Rannells, Kayleigh McKee and Sean Rohani.[37][21] According to the trailer and the synopsis by Max, Finn, Jake, Princess Bubblegum and Marceline the Vampire Queen appear in the series.[21] In the original Adventure Time series, the character Prismo was voiced by Kumail Nanjiani. However, due to a communication mishap with Nanjiani's representatives, the producers of Adventure Time believed that the actor was not available to reprise his role for Fionna and Cake, so they recast the part. Nanjiani later expressed his frustrations on Twitter, writing: "[Prismo is] one of my absolute favorite characters I've ever had the honor of playing... I would have [voiced him] for free... [The situation] is ridiculous."[38] In the original series, Prince Gumball was voiced by Neil Patrick Harris and later Keith Ferguson;[8][39] Justin Roiland originally voiced Earl of Lemongrab and he was replaced by Jinkx Monsoon.[40]

Some known cast of the rest of characters are as follows. In the first two episodes, there are Robbie Daymond (Ice Prince), Niki Yang (BMO), Maria Bamford (Starchy), Chelsea Peretti (Queenie), Phil LaMarr (Dog Tourist), Jack Pendarvis (Dirt Beer Guy), Dan Mintz (TV), Dee Bradley Baker, Erica Mendez (Skater Fairies & Ice Scout #1), Cristina Vee (Skater Fairies & Ice Scout #2), Jeff Bennett (Evil Choose Goose & Choose Bruce). For episodes 3-4, there are Grey DeLisle (Ice Cream Queen), Sharon Horgan (Minerva-bot), Marc Maron (Squirrel), Jim Cummings (The Owl), Melissa Villaseñor (Rainy), Andrew Daly (Kheirosiphon & Wyatt); for the episode 5, there are James Kyson (Big Destiny), Mickey Zacchilli (Little Destiny), Tiffany Wu (Jay), Eric Bauza (Peanut), Nia Castro (Bonnie). For episodes 7-8, there are Jenny Slate (Huntress), Stephen Root (Martin Mertens), Erica Luttrell (Hana Abadeer), Billy Brown (Vampire King), Steve Little (virtual assistant of Peppermint Butler), Cole Sanchez (Moderator & Heckler #2), David McCormack (Orbo). In the last two episodes, there are Sean Giambrone (Shermy), Imani Hakim (Beth), Iggy Craig (Casper) and Rosie Brand (Nova).[41]

As with Adventure Time, Rough Draft Korea and Saerom Animation worked on different episodes of the spin-off series. In an interview with Animation Magazine, Adam Muto revealed that for this spin-off, the writers had to plot out the season beforehand; this approach was required of them by Max, and it contrasted with how the writers had approached storylines when working with Cartoon Network. Muto noted that the production was challenging because there was not much overlap in terms of color palette and backgrounds, as each episode is basically its own new world. Approximately 50 crew members from Cartoon Network Studios worked on the pre- and post-production side; the production started in 2021, during the time of the COVID-19 pandemic. Most of the team was based in California, but some animators were as far away as Russia and Japan; during the height of the pandemic, about 90 percent of the work was done remotely until the studio reopened in 2022.[3] Production of Adventure Time: Fionna and Cake ended on December 9, 2022.[42][43]

Former Adventure Time crewmembers Rebecca Sugar, Somvilay Xayaphone, and Patrick McHale, as well as Distant Lands composer Amanda Jones, returned to compose songs for the spin-off.[3][30] The series intro and end credits were storyboarded by Steve Wolfhard and animated by Nick Cross,[44][45] that latter of whom also animated the silent film sequence in the fourth episode "Prismo the Wishmaster" and the Orbo scenes of the eighth episode, "Jerry".[46][47] The song "Not Myself", written by Zuzu, is the intro song for the first episode "Fionna Campbell";[48] Sugar wrote two songs, "Part of the Madness" and "Cake on the Loose".[49][50] For the sixth episode "The Winter King", McHale and J. R. Kaufman wrote two songs "Winter Wonder World" and "Baked with Love",[51][52] and the animation sequence of "Winter Wonder World" was directed by Alex and Lindsay Small-Butera (SmallBü),[53] who previously guest animated two Adventure Time episodes, "Beyond the Grotto" and "Ketchup".[54][55] The eighth episode "Jerry" features a song "Everything in You", written and performed by Half Shy, who also wrote the song "Monster" from the Distant Lands special "Obsidian".[56] The 3D game sequences of the last two episodes were designed and animated by Louie Zong.[57]

Fan art of Finn (right) and Fionna (left)

As of September 2023, Fionna and Cake has a 100% approval rating on Rotten Tomatoes based on 10 reviews.[60]

Before the debut, Chase Hutchinson of IGN commented that Fionna and Cake sidesteps mawkishness and embraces a distinctly unsentimental tone, which he found invigorating. He argued that "it ponders how the complex characters may have changed since we last saw them and, in recurring meta interjections, how its creators may have changed themselves".[61] Kaiya Shunyata of RogerEbert.com said that the series let viewers "fall in love with different versions of characters that viewers initially fell in love with 13 years ago" and argued that the series remains "true to the show's fans".[62] Coleman Spilde of The Daily Beast said the series is far from a "nostalgia-baiting cash grab" but is rather a "marked expansion of the Adventure Time lore", and stated that the series replicates the "soothing character design and animation style" from Adventure Time. He also argued that the series has "meta fun at its own history" and said that it succeeds where Adventure Time "faltered".[63]

Jake Kleinman of Inverse said that the series moves the "entire franchise forward by leaps and bounds", called it one of the "most emotionally mature entries" in the franchise, and added that the series is, at its heart, "a story about the heartbreak of growing up".[64] Nick Valdez of ComicBook.com stated that the series ushers in a "whole new era of the franchise" by focusing on "darker tones" and called it a "series made with fans of the original series in mind".[65] Aryan Khanna noted that the series shifts into mature storylines while maintaining the original charm, comparing it with The Legend of Korra and some other series reboots for new generations; Khanna argued that this results in a fascinating combination of existential inquiry, appealing adventures, and whimsical comedy.[66] Reuben Baron of Paste said that the series is "targeted specifically at a young adult audience," called it a show for "hardcore" fans, and compared the first two episodes to Bee and Puppycat and Steven Universe Future. He also stated that the use of multiverses in the series resembles Loki and Spider-Man: Across the Spider-Verse, and called the series a "worthy continuation of the legendary cartoon".[67]

Samantha Puc of Polygon and James Factora of Them both gave praise to the series for its queer representation—mainly through the romantic relationship between Marshal Lee and Gary Prince. Puc noted the intercutting between the relationships of Gary and Marshall Lee, and their gender-swapped counterparts Bubblegum and Marceline, in "The Star", commenting that "they are always written as each other's romantic destinies".[68] Factora contrasted Gary and Marshall's "unabashedly gay relationship" with "how contrivedly heterosexual" the early seasons of Adventure Time could be at times.[69] Puc similarly contrasted Fionna and Cake's casual presentation of "queerness as a given in its parallel universes" with the earlier Adventure Time, which had to "[fight] hard for increased and visible queer inclusion".[68]

Muto noted that, instead of him actively asking for it, the LGBTQ+ representation came out of the involved writers and artists themselves, who want their identities to be expressed and portrayed, and it became more overt in Steven Universe and some following shows.[27] After the finale, about Gary and Marshall's romance as well as Bonnie and Marcy's rivalry, Susana Polo of Polygon argued that "a franchise once imprisoned by heteronormative censorship gave its fan-beloved queer couple multiversal staying power."[70]