Fern: Adapting the Green Knight in Adventure Time

Sir Gawain and the Green Knight, the Middle English alliterative Arthurian poem, has long captured the imagination of audiences, medieval and modern. Recently, Valiant Comics has adapted the Sir Gawain and the Green Knight into a comic titled “Immortal Brothers: The Tale of the Green Knight” and brought the poem to modern audiences (2017). The same year, Emily Cheeseman adapted Sir Gawain and the Green Knight into a graphic novel (2017), which was funded by Kickstarter and which is now publicly available online.

Cover image from Emily Cheeseman’s Gawain and the Green Knight (2017).

Film adaptions of Sir Gawain and the Green Knight have also emerged in modern times, including Steven Weeks’ two movies based on the medieval story: Gawain and the Green Knight (1973), and then about a decade later, The Sword of the Valiant: The Legend of Sir Gawain and the Green Knight (1984), which famously features Sir Sean Connery as the Green Knight. While Weeks draws primarily from Sir Gawain and the Green Knight in his film adaptations of the medieval poem, he also borrows from other Arthurian legends, such as the tale of Sir Gareth in Thomas Malory’s Le Morte d’Arthur and Yvain, the Knight of the Lion by Chrétien de Troyes.

The Green Knight (Sean Connery) in Stephen Weeks’ “The Sword of the Valiant: The Legend of Sir Gawain and the Green Knight” (1984).

Moreover, last year a new film adaption of the poem, titled The Green Knight (2021), directed, written, edited, and produced by David Lowery, was released in theaters. This recent movie adaption of Sir Gawain and the Green Knight drew both praise and opprobrium from critics, prompting me to view and write my own review of the film. The Green Knight stars Dev Patel as Gawain, a nephew of King Arthur in this adaptation, who embarks on an epic quest to test his chivalry and confront the Green Knight.

The Green Knight (Ralph Ineson) in David Lowery’s The Green Knight (A24 Films, 2021).

But today, as I previewed in my previous post on adaptations of Beowulf in modern cartoons, I want to discuss the introduction of a character adaptation of the Green Knight in the final season of Cartoon Network’s Adventure Time. The episode that features and centers the Green Knight is called “Seventeen” (Season 10 Episode 5), in which the plot borrows substantially from the medieval alliterative poem, despite significant redactions and reworking on certain characters and themes from the source text.

Opening image for Adventure Time‘s S10E5 “Seventeen” (2017).

As in the Middle English romance, the episode begins with feasting and a celebration. In Sir Gawain and the Green Knight, King Arthur and his court at Camelot are celebrating Christmas and Yuletide. In Adventure Time, the celebration centered on the 17th birthday of Finn the Human, who is also the main hero and one of the primary protagonists of the show, at Princess Bubblegum’s court in the Candy Kingdom. In both the medieval poem and modern cartoon series, the Green Knight rudely barges into court, unannounced, uninvited and riding on his green horse, before offering a green battle axe and proposing a dangerous challenge.

The Green Knight barges into the Candy Court in S10E5 of Adventure Time, “Seventeen” (2017).

In “Seventeen” when the stranger enters, Finn exclaims “you’re green,” to which the guest responds “I’m the Green Knight.” Like in the medieval poem, Adventure Time‘s Green Knight is exceedingly green, from his armor and clothes, to his hands and face, and even his mount and weapon are all shades of green. The special attention the cartoon gives the green axe and green horse pays homage to the Middle English romance, which contains detailed descriptions of the green man, his green axe and his green steed.

The mysterious Green Knight in S10E5 of Adventure Time, “Seventeen” (2017).

In both the television series and Middle English poem, the Green Knight’s arrival is shrouded in anticipation and ladened with suspense. Just as in the original poem, the Green Knight in Adventure Time is a mystery knight, come to challenge the champion and test his opponent’s heroism and mettle. In keeping with its source, Adventure Time makes games central to the episode, beginning with the very game featured in the original poem.

The Green Knight gives Finn a birthday axe in S10E5 of Adventure Time, “Seventeen” (2017).

In Adventure Time, since it is Finn the human’s 17th birthday party, when the Green Knight arrives at the court of Princess Bubblegum, he gifts his green axe to Finn for the occasion. The Green Knight greets Finn by saying: “And before you ask, of course I brought you a birthday present. It’s a battle axe.” The Green Knight follows up with a cryptic caveat “But only if you play me a game for it.” As Gawain does in the Middle English romance, Finn accepts the battle axe and the Green Knight’s challenge, deciding to game with the mysterious guest.

Finn beheads the Green Knight in S10E5 of Adventure Time, “Seventeen” (2017).

As in Sir Gawain and the Green Night, the first birthday contest in “Seventeen” is a weird beheading game. When Finn asks which game they will play, the Green Knight describes the game: “Oh this game is called all you have to do is strike me with it and it is yours.” Finn struggles with the idea of “axing a stranger” but soon has a revelation. Noting the absence of his partner, Finn assumes that the mysterious Green Knight is nothing more than a birthday prank orchestrated by his best friend Jake, so the hero plays along and is unfazed by the uncanny strangeness of the proposed game. Finn deals what appears to be a death-dealing blow to the neck, decapitating the Green Knight, much like Gawain does in the original poem.

Green Knight grabs its severed head as Jake arrives in S10E5 of Adventure Time, “Seventeen” (2017).

Again, as in its source, the Green Knight in “Seventeen” proves to be some sort of undead being, able to simply pick up and replace his head after his beheading. It is at this point that Jake arrives, signaling that the Green Knight is not an elaborate birthday hoax by Jake, and what was planned as a fun birthday turns into a fight for his life. Citing fairness, the Green Knight isolates Finn from the rest of his friends so that they cannot aid him, or warn him of any foul play on the part of the Green Knight.

Unlike in the Middle English romance, in “Seventeen” Finn asks for alternative games rather than allowing the Green Knight to return an axe stroke to his neck. This marks the major point of divergence in what follows as a loose adaptation. The stakes are set: if Finn wins, the Green Knight will reveal the mystery of his identity and the Green Knight makes plain his reward, stating, “if I win, chop, chop.”

The green horse interferes with the first game in S10E5 of Adventure Time, “Seventeen” (2017).

The Green Knight is able to win the first contest through deception and subterfuge, ideas central to the source text as well, and then the Green Knight allows Finn to win the second contest without competing at all, undercutting his heroism. This ultimately proves the only game in which Finn defeats his opponent. Again, the Green Knight has a trick up his sleeve, this time the plan is to allow Finn to expend his energy and strength, giving the Green Knight the upper hand in the decisive game between Bubblegum’s champion and the mysterious guest.

Green Knight is revealed as Fern in S10E5 of Adventure Time, “Seventeen” (2017).

Finn recognizes the trick immediately, but Finn believes his “robot arm” will continue to provide him with an advantage in the final contest of strength: an arm wrestling match. While Finn is able to compete with the Green Knight until the first mystery is revealed, once the hero learns that the Green Knight is none other than Fern, his formerly deceased, plant-form doppelgänger, he becomes overwhelmed causing him to lose their last game. The surprise of the Green Knight’s identity disarms the hero and allows Fern to easily defeat Finn. Fern, in Green Knight form, smashes his enemy upon the table, breaking it, and leaving Finn on the floor, vulnerable and in shock, as the Green Knight approaches, axe raised and ready to deliver a fatal blow.

Finn as he is about to receive an axe stroke in S10E5 of Adventure Time, “Seventeen” (2017).

These additional games replace the hunting and bedroom games featured in the Middle English romance, but the narrative of “Seventeen” nevertheless realigns with the original plot as the hero ultimately fails and appears as if he is about to be beheaded by his opponent. In the medieval poem, the Green Knight is revealed to be Bertilak, the lord who houses Gawain and whose wife seduces him. But the double reveal includes the revelation the it was Morgana Le Fay (2446), a witch and King Arthur’s half sister, who sent the Green Knight to Camelot to test the Knights of the Round Table and frighten Queen Guenevere.

Uncle Gumbald, Aunt Lolly & Cousin Chicle are revealed in S10E5 of Adventure Time, “Seventeen” (2017).

Similarly, in Adventure Time, the Green Knight is a servant of disgruntled, royal relatives. In “Seventeen,” the Green Knight is called off by his own steed, which is shown to be a mechanical horse in which three treacherous relations of Princess Bubblegum are hidden: Uncle Gumbald, Aunt Lolly and Cousin Chicle. The double mystery aspect of the cartoon mirrors the medieval poem’s dual reveal at the end of narrative, in both cases returning focus to intrafamily power struggles over the throne while simultaneously demonstrating the limitations of chivalry and the dangers of hubris. By the end, in both Sir Gawain and the Green Knight and “Seventeen” the royal champions are bested by the Green Knight, although in Adventure Time, the Vampire Queen Marceline is there to step in and scare off the intruders, causing the Green Knight to retreat into the night.

Marceline vs the Green Knight in S10E5 of Adventure Time, “Seventeen” (2017).

The way in which Adventure Time creatively adapts and reinvents Sir Gawain and the Green Knight for a broad modern audience carries forward the medievalism from “The Wild Hunt” (Season 10 Episode 1). Although at times the episode deviates dramatically from its source, Adventure Time makes the complex (at times enigmatic) medieval story both accessible and comedic, while retaining some of the key aspects including the fraught presentation of chivalry and heroism, thereby helping to set the stage for future generations of medievalists.

The Green Knight: Another Medievalist’s Review

After almost forty-years without a major motion picture adaption, David Lowery’s The Green Knight (2021) was much anticipated and made quite a splash, but pulled mixed reviews from scholars and critics.

The film’s primary source material, the medieval alliterative poem Gawain and the Green Knight, happens to be my personal favorite work in Middle English, my favorite Arthurian romance and my second favorite work of medieval literature following only Beowulf. Indeed, because I find both the story and poetics so fascinating, my very first blog explored possible functions of the bob and wheel in Gawain and the Green Knight. I have always read the poem as a tale of a hero brought low and the three conclusions offered by the Green Knight, Gawain himself and King Arthur’s court provide a variety of interpretations from recognition of the hero’s humanity to his feelings of failure and shame to the merriment and celebration of his chivalry by king and court.

Images of Arthur, Guinevere, Gawain & the decapitated Green Knight in British Library, Cotton Nero MS a.x f.94v

The poem’s concatenation on themes (such as schame “shame” emphasized in the “bob and wheel” structure) drives these points home but also mimics the psychological experience of anxiety and a nagging, internal monologue. The mystery of the enigmatic Green Knight haunts the entire tale. The parallelism, especially between Gawain and the Green Knight, as well as the playful emphasis on games, exchanges and hunts produces a thrilling, at times dizzying, narrative that is rich with implication and subterfuge.

Gawain confronts the Green Knight in the Green Chapel in British Library, Cotton Nero MS a.x f.129v.

Often with modern film adaptions of medieval literature, directors and producers make what I consider to be a fatal mistake of perceiving virtually every medieval tale as an action movie. In my view, this fundamental bias plagues every film adaption of the poem to date, and when I learned Lowery’s The Green Knight (2021) was under production and forthcoming, I will admit I was rather skeptical. However, even from the trailer, it seemed—at least to me—this adaption of the medieval poem might get some things right which previous film adaptions like Stephen Weeks’s Sword of the Valiant: The Legend of Sir Gawain and the Green Knight (1984) staring the late Sean Connery as the Green Knight did not seem to pick up on. When The Green Knight was released in theaters, I went to see it, making it the only film I have seen in a movie theater since the outbreak of the COVID-19 pandemic. Thankfully, it did not disappoint.

Many other medievalists and film critics have reviewed this much-anticipated film, some wishing there was more of an action movie component, others criticizing the Mallory-esque titling and expanded episodes in the film, and still others praising the film’s orientation as a “coming of age” tale, its attention to detail and how film makes themes such as Gawain’s shame and chivalry intriguing to modern audiences. Personally, I loved it.

Dev Patel stars as Gawain in the film David Lowery’s The Green Knight (A24 Films, 2021).

There were some odd decisions which I did not quite understand such as the introduction of a talking fox (a feature of medieval beast fables, but appearing nowhere in the film’s Middle English source). Similarly, demoting Gawain from the status of knight made little sense to me and rather than as an egoistic knight demonstrating hubris, Gawain appears as a desperate and neglected aspirer doomed to a life of psychological trauma. The humanization of Gawain was apparent throughout, and Dev Patel gives a stunning performance in his role as Gawain, but the arch of his character is somewhat flattened due to these changes in Gawain’s status and characterization. Still, overall, this movie hits the nail on the head for me.

The Green Knight (Ralph Ineson) upon entering Arthur’s court in David Lowery’s The Green Knight (A24 Films, 2021).

In particular, the Green Knight is in full green man form and spot on. The story is presented not as an action movie but as a psychological thriller. Emphasis on games, exchanges and hunts is imbedded throughout the movie. The visual components from cinematography to mise-en-scène are eye-popping as the film frequently displays surreal imagery to create a psychedelic mysticism associated with the Green Knight as well as Morgan Le Fay and Gawain’s quest as a whole. Additionally King Arthur and Queen Guinevere are shown as diminished in their old age, and this generates a sort of magical realism within the film.

Lady Bertilak (Alicia Vikander) gifting the magical green girdle to Gawain (Dev Patel) in Lowery’s The Green Knight (A24 Films, 2021).

For some, the movie will perhaps be too vulgar or too artsy-fartsy. Others, expecting to watch Gawain’s epic battles, may likewise be disappointed. Nevertheless, I agree with reviewers who observe a notable affinity between the medieval source and this modern rendition. In my opinion, Lowery’s The Green Knight represents a modern film adaption like few others: one that has its finger on the pulse of the medieval poem which inspired its creation.

Richard Fahey
PhD in English
University of Notre Dame


Digital Text

Gawain and the Green Knight. Middle English Compendium: Middle English Poetic Corpus (2/2/2019).


Modern English Translation

Deane, Paul. Sir Gawain & the Green Knight. Alliteration.net: The Pearl Poet (1999).

Digitized Manuscript & Shelfmark

London, British Library, Cotton Nero MS a.x f.94v-130r.

Further Reading

Brody, Richard. “The Green Knight, Reviewed: David Lowery’s Boldly Modern Revision of a Medieval Legend.” The New Yorker: The Front Row (8/3/2021).

Cybulskie, Danièle. “Medieval Movie Review: The Green Knight.” Medievalists.net (7/2021).

Dahm, Murray. “Sir Gawain and the Green Knight in the Movies.” Medievalists.net (1/2021).

Fahey, Richard. “Bobbing For Answers.” Medieval Studies Research Blog. University of Notre Dame: Medieval Institute (2/26/2015).

Grady, Constance. “The Magic, Sex, and Violence of the 14th-century Poem Behind The Green Knight.” Vox (7/29/2021).

Harty, Kevin J. “The Green Knight, dir. David Lowery (2021).” Medievally Speaking (8/10/2021).

Hilmo, Maidie. “The Colors of the Pearl-Gawain Manuscript: The Questions that Launched a Scientific Analysis.” Medieval Studies Research Blog. University of Notre Dame: Medieval Institute (1/12/2014).

Johnson, Weldon B.How ‘The Green Knight,’ Set in the Days of King Arthur, Takes a Modern Look at Masculinity.” Arizona Central (7/28/2021).

Lawson, Richard. “The Green Knight Is This Summer’s Best Medieval Meditation on Death.” Vanity Fair (7/28/2021).

Martin, Elyse & Sean Rubin. “Chivalry and Medieval Ambiguity in The Green Knight.” Tor (8/10/2020).

—. “Medievalists Ask Five Questions About A24’s The Green Knight.” Tor (6/1/2020).

Nelson, Ingrid. “The Green Knight” and The Green Knight.” Medium.com (7/28/2021).

Olsen, MarkChang, JustinYamato, Jen. “Did You Love or Loathe ‘The Green Knight’? Either Way, You’re Not Alone.” Los Angelos Times (8/7/2021).

Ouellette, Jennifer.Review: The Green Knight Weaves a Compelling Coming-of-age Fantasy Quest.” Ars technica (7/31/2021).

Perry, David M. & Matthew Gabriele. “The Green Knight Adopts a Medieval Approach to ‘Modern’ Problems.” Smithsonian Magazine (8/23/2021).

Trigg, Stephanie. “The Poem Behind The Green Knight.” Pursuit (8/27/2021).

Wilkinson, Alissa. “The Green Knight is Glorious and a Little Baffling. Let’s Untangle It.” Vox (7/30/2021).