Dev Patel doesn't quite fit the role of Sir Gawain any more than he did as David Copperfield, but it isn't really his fault that The Green Knight feels like a jumbled-together collection of scenes; writer/director/editor David Lowery is to blame for this. Early in the film, King Arthur (Sean Harris) asks Gawain to recount some experiences so he can get acquainted with him. Gawain says he doesn't have any stories to share, and two hours later, that’s still essentially true—he has only a few disconnected moments that don't add up to something meaningful. The movie also suffers from poor pacing; it takes an awfully long 15 minutes just to introduce the Green Knight (voiced by Ralph Ineson), but when he presents his challenge, Gawain immediately accepts without allowing anyone else a chance to decline. This situation had real potential for dramatic impact, and Lowery should have explored it more fully; alternatively, perhaps he's aware of how underwhelming his version of the Green Knight is and wants to rush through him as quickly as possible until he has to show up again at the end. Sean Connery’s portrayal of the Green Knight in Sword of the Valiant looks like a mix between Santa Claus and Saint Patrick, but at least that character feels real and is played by an excellent actor—a million times better than the wooden, CGI-like version Lowery created. This Green Knight isn't just visually unappealing; he’s also portrayed as unintelligent. He carries a letter explaining his purpose; this letter is read aloud by the Queen in a strange voice, like she’s possessed or something. Is the Knight, whose severed head can talk, speaking through her? And if so, what's the reason for the letter then? Naturally, after the disappointing ending that doesn't resolve anything (including an example of "It's A Wonderful Plot," similar to Willem Dafoe’s experience in The Last Temptation of Christ), a more pressing question is, what was the point of this film? This movie feels like the work of a director who's trying to pull something off; Lowery not only casts a non-traditional actor in the lead role but also uses queerbaiting with a kiss between Patel and Joel Edgerton—something that actually happens in the original 14th-century poem, so it’s hardly groundbreaking. The way this kiss is presented is especially troubling because it makes Gawain seem prejudiced.

Source on TMDB