Most fantasy adventures feel less like filmed folktales than somewhat parochial expressions of the cinematic moment at which they were created. Even unassailable classics of the genre such as The Thief of Bagdad, Excalibur, and The Lord of the Rings feel unmistakably like features made in 1940, 1981, and the early 2000s, respectively. The transportive power of lavish production design and dazzling visual effects are inevitably offset by anachronistic tells that betray the illusion: We are not witnessing a story out of time, but a work of pop entertainment presented in a manner intended to maximize its accessibility, despite the presence of knights, wizards, and more fantastical elements. Granted, the results can be thrilling when the filmmaker’s vision is conceptually sound and skillfully executed. When it is not, well… you get Beowulf (2007), which rendered the most famous work of Old English literature as a series of video-game boss battles.

Blessings, then, to writer-director David Lowery’s marvelously weird new feature, The Green Knight, for being that exceedingly rare fantasy film that feels like it slouched forth from some Jungian folkloric netherworld. To even describe it as a “fantasy film” feels misleading. In the context of our present era of spectacle-stuffed blockbuster franchises, such a descriptor implies motley fellowships of outsider heroes and massive, CGI-abetted battle sequences. The Green Knight has neither, being the story of one person’s lonely, faltering journey to meet their destiny. Surreal and mutinously languorous, Lowery’s acid-trip take on Arthurian legend has more in common with Pier Paolo Pasolini’s Greek-myth features (Oedipus Rex, Medea) than it does with J.R.R. Tolkien or T.H. White. It is both exhilaratingly archaic and thoroughly modern, a daring attempt to tell the anguished story of a man struggling to understand who he is – and who he should be – via the otherworldly logic of rune-etched myth.

Adapted with a surprising degree of faithfulness from the 14th-century chivalric romance Sir Gawain and the Green Knight, Lowery’s film unfolds in a gray, chilly kingdom that is far removed from the alabaster Camelot of storybook fame – although it feels just as timeless, in its way. Young knight-in-training Gawain (Dev Patel) is the heir apparent of the childless king (Sean Harris) and queen (Kate Dickie), being the oldest son of the king’s sister (Sarita Choudhury). Gawain is also something of a ne’er-do-well, spending most of his time drinking and tumbling his favorite courtesan, Essel (Alicia Vikander). During the king’s annual Christmas Day feast, however, Gawain finally receives an opportunity to demonstrate his worthiness. A towering knight (Ralph Ineson) with skin like mossy tree bark appears in the court and challenges the king’s bravest man to face him in a duel. He adds a curious condition, however: Any opponent who lands a strike must journey to the Green Chapel in one year’s time and submit himself to the same injury.

The assembled knights hesitate, so Gawain leaps at the chance to prove his quality, accepting the king’s fabled sword as his chosen weapon. The Green Knight, however, puts up no resistance, laying down his colossal battle ax and calmly presenting his neck to Gawain’s blade. Bewildered but determined, Gawain cuts off the knight’s head with one blow. To the shock of the entire court, the Green Knight stands up, retrieves his severed head, and rides away, cackling triumphantly. Perhaps thinking it a bit of Yuletide theater, the feast’s guests applaud in delight, and Gawain’s reputation for strength and valor seems to be solidified by the incident. Yet the knight’s growling words echo in Gawain’s mind: “One year hence.”

The wheel of the seasons turns, and suddenly it is Christmastime again. Gawain’s duel with the Green Knight has become the stuff of local legend, inspiring alehouse gossip and children’s puppet plays. When the increasingly infirm king appears to see his nephew off on his journey to the Green Chapel, Gawain is taken aback: “Was it not just a game?” “Perhaps,” the king responds cryptically, “but it is not yet complete.” Gawain’s mother ensures that he is properly outfitted for his mission, garbing him in a new mail shirt, yellow cloak, and emerald sash, the latter secretly sewn with a protective talisman. In fact, the king’s sister – who, consistent with most modern Arthuriana, seems to be a conflation of two different figures, Morgause and Morgan le Fay – may have had a hand in manipulating the whole affair. During the previous Christmas feast she was glimpsed inscribing the Green Knight’s words as part of some elaborate pagan spell. Was Gawain’s quest engineered to secure his knightly reputation and thus his claim to the throne? As with almost everything in The Green Knight, the truth of the matter is ambiguous, but the murky machinations of Gawain’s mother serve to underline that the would-be knight must learn to write his own fate.

Like most chivalric quests, Gawain’s journey is highly episodic, not so much a tidy dramatic narrative as a halting sequence of peculiar encounters rich in mythic symbolism. (To emphasize the point, Lowery announces each phase of the quest with a twee Chaucerian intertitle.) These encounters start out mundane enough, as Gawain is waylaid by a trio of grubby bandits, but thereafter they seem to escalate in their mystical strangeness. Between a virgin saint, a talking fox, and a tribe of ethereal giants, Gawain is alternately distracted and dissuaded from his quest, as the Christmas Day deadline for his rematch with the Green Knight creeps ever closer. The most subtle threat to Gawain’s oath lurks within a remote castle ruled by a garrulous lord (Joel Edgerton) and a lady (Vikander) who uncannily resembles the knight’s beloved. Both husband and wife are gracious hosts, and their estate is wondrous and inviting – perhaps too inviting. The lord’s affable but blunt questions seem to pry at the edges of Gawain’s beliefs and identity. What does he hope to find? Why is honor so important to him? If a quest can turn a man into a knight, is it not a kind of magic?

Lowery (Pete’s Dragon, A Ghost Story) retains the most pivotal set pieces from this 600-year-old story but also adds his own hallucinatory embellishments around the edges. Passing allusions in the original verse are here expanded into encounters studded with redolent pagan and Christian imagery. The forlorn mythic Britain summoned forth by the film’s superb design team – including production designer Jade Healy, set decorator Jenny Oman, and costume designer Malgosia Turzanska – feels like a realm perched on the precipice between the old and new. Woodsmen fell the last remaining trees in the blasted countryside surrounding Camelot, but such culling does not prevent the Green Knight from striding straight into the heart of the king’s court, holly bough in hand. Gawain’s shield – an image of the Virgin Mary on one side, a magic pentacle on the other – embodies the duality of a world that rumbles with unsettled tensions, much as Gawain himself has not resolved what kind of man he intends to be.

The most significant alteration that Lowery has made to the original tale lies at its end. While the poem concludes in a joyful reversal that reflects the spiritual renewal of the New Year, the filmmaker opts for a more sober and uncertain ending that evokes no less a film than The Last Temptation of Christ (1988). Like that feature, The Green Knight restores some of the thorny, quivering humanity to its protagonist’s story, using ancient motifs to vividly express the psychological and philosophical conflicts that bedevil him. The film’s language might have the weight of centuries, but its concerns feel strikingly post-medieval. How can one be true to oneself? What does it mean to live with integrity?

In his mesmerizing way, Lowery reframes these questions in a manner that enhances their unruly resonance for a contemporary audience more accustomed to fantasy tales that follow a smooth, well-trod path. The Green Knight invites the viewer to lose their way in a truly unfamiliar world, and thereby learn something of themselves. It tingles with the same ripe, slightly dangerous sense of possibility that author Hilary Mantel beguilingly captured in a passage from her seminal historical novel Wolf Hall: “In the forest you may find yourself lost, without companions. You may come to a river which is not on a map. You may lose sight of your quarry and forget why you are there.”

Rating: B+

The Green Knight opens in select theaters on July 30, 2021.