Adventure Time: Fionna and Cake


Adventure Time: Fionna and Cake is an American adult animated television series developed by Adam Muto for the streaming service HBO Max. It is a spin-off of the Cartoon Network series Adventure Time and the third main installment in the Adventure Time franchise. The series debuted on August 31, 2023, and the second season premiered on October 23, 2025.
The series follows the eponymous Fionna and Cake the Cat, alternate-universe versions of Adventure Time's main characters: Finn the Human and Jake the Dog. Fred Seibert and Sam Register serve as executive producers alongside Muto, who himself served as showrunner for the last six seasons of Adventure Time and oversaw production of the Distant Lands specials.

Synopsis

Where Adventure Time follows the adventures of Finn the Human and Jake the Dog, Fionna and Cake follows Finn and Jake's gender-swapped counterparts, Fionna the Human and Cake the Cat. The spin-off centers around Fionna Campbell, a young woman in a universe without magic who lives with her cat, Cake. In the first season, they have multiversal adventures with Simon Petrikov, a character who for most of Adventure Time had been known as the Ice King, and with Huntress Wizard in the second season.

Cast

Main

Season 1 (2023)

Season 2 (2025)

Background

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. Reception to the gender-swapped characters was so positive that the Adventure Time producers decided to write the characters into the series; they debuted in Season 3's "Fionna and Cake", on which Allegri worked. 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."

Production

Development

After the 2018 finale "Come Along with Me", a first spin-off series of Adventure Time: Distant Lands debuted in 2020; before the latter's finale in the next year, HBO Max announced that a gender-swapped spin-off series was in production. The Adventure Time: Fionna and Cake series was developed specifically with the young adult demographic in mind, according to Suzanna Makkos, an executive for both HBO Max and Adult Swim. In the United States, the limited series received a TV-14 certification based on the adult content, compared to Adventure Times TV-PG rating. Longtime Adventure Time and Distant Lands executive producer Adam Muto returned to produce the limited series and also served as the showrunner, with Fred Seibert and Sam Register in partnership with Cartoon Network; 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.
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. Distant Lands is a limited series of four loosely connected vignettes, Fionna and Cake, on the other hand, is a more united story. While Finn is a selfless and energetic hero, Fionna is more ordinary, realistic, and without magic; while Jake is a lazy dog of magic powers, Cake lacks such powers and begins the series as a regular house cat. 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 Lee share the look of gray vampire skin; in Fionna and Cake, Marshall Lee is with dark skin as a human character. As to Jake's uncertain death, Muto decided to leave it ambiguous.

Casting

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. In the original Adventure Time series, the character Prismo was voiced by Kumail Nanjiani. Due to a miscommunication from Nanjiani's representatives, the crew believed that he was not available and they recast the part during the first season with Sean Rohani, and Nanjiani later returned as Prismo again in season 2. In the original series, Justin Roiland voiced Earl of Lemongrab and he was replaced by Jinkx Monsoon, who later co-voiced with Cree Summer as the Lemoncarbs, the gender-swapped human version of Lemongrab as twin sisters.
Further recasts happened for season 2. Ashly Burch voices Huntress Wizard, in Adventure Time was previously voiced by Jenny Slate and Maria Bamford. As a fan and previously a writer of the show itself, Burch said that Huntress Wizard is important to her and she wanted to do her justice; Adam Muto did an open audition for the role, not knowing Burch auditioned until her audition was listed. In addition, Marshall Lee and Gary Prince, being voiced in the first season by Donald Glover and Andrew Rannells respectively, were also recast with Kris Kollins and Harvey Guillén. Asked about the cast changes, Muto mentioned the crew wanted to do different takes on established characters without making them sound like their previous voice actors. Muto also expressed difficulties with the recasting of characters, due to the unavailability of certain actors and the changes of modern streaming production. Frank Collison provided the voice for the Cosmic Owl in the series, following the death of M. Emmet Walsh in 2024. Walsh's death contributed to the decision to have the character temporarily killed off.

Animation

As with Adventure Time, Saerom Animation, Rough Draft Korea and later Digital eMation 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 HBO 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. For the sixth episode "The Winter King", the animation sequence of the song "Winter Wonder World" was directed by Alex and Lindsay Small-Butera, who previously guest animated two Adventure Time episodes, "Beyond the Grotto" and "Ketchup". 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% of the work was done remotely until the studio reopened in 2022.

Release

The first season of Adventure Time: Fionna and Cake debut on August 31, 2023; after the season finale, the series was renewed and the second season premiered on October 23, 2025.
Outside the United States, the series debuted on the same day in Australia on the streaming service Binge, and later by Fox8 on September 1. The series also premiered on Cartoon Network in Canada on September 15. On November 19, the series debut followed the release of HBO Max in Taiwan and Hong Kong; the series also released later in Macao on October 15, 2025. In South Korea, it was released on March 21, 2025 through the streaming service Coupang Play, along with other HBO Max original programs.

Reception

Critical reception

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". 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. 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. Around September 2023, the first season of Fionna and Cake received a 100% approval rating on Rotten Tomatoes based on 10 reviews, and 78/100 on Metacritic based on 5 reviews.
Sabina Graves said that season two dances between both worlds, building out Finn’s B-plot on a collision with Fionna’s world; she argued that, in a world of grabby capitalism, Fionna and Cake explores the importance of community roles and they cultivating community care is what makes the show’s conceit work. Julian Lytle concluded that the season is like a dramedy with themes of struggling adulthood and magical trips, acknowledging the strong voice acting.

LGBTQ+ representation

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 Marshall Lee and Gary Prince. Puc noted the intercutting between the relationships of Gary and Marshall Lee versus their gender-swapped counterparts Bubblegum and Marceline in "The Star", commenting that "they are always written as each other's romantic destinies". Factora contrasted Gary and Marshall's "unabashedly gay relationship" with "how contrivedly heterosexual" the early seasons of Adventure Time could be at times. 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 " hard for increased and visible queer inclusion".
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. 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."