The arthouse fantasy “The Green Knight” begins with a word from an off-camera narrator who disappears right after he repositions the Christian allegory of “Sir Gawain and the Green Knight” as a secular fairy tale.
In this pompous introduction, which sounds like a stuffier version of Mako’s preface to “Conan the Barbarian,” Gawain (Dev Patel) is compared with his uncle King Arthur (Sean Harris), though we are told that Arthur’s legend is a story for another time. Gawain is also a different kind of seeker, and the limits of his vision will come to define not only the meaning of his story but how it is told.