The question of adaptation has been an open one in culture since people began doing them in other media, as it were. Just like the fact that sex wasn't invented in 1968, this is not a 20th century or now 21st century phenomenon. The Odyssey, the epic poem ascribed to Homer, was most likely just a written rendition of what had been oral tradition for many years or even centuries before the point where he is acknowledged to have written it (~8th century BCE.) But legends of this sort have been the subject of books, plays, operas (one of my favorite moments in Amadeus refers to this quandary, when Wolfgang argues against constantly using the same, old subjects) and more recently, film and TV. No one is ever going to get it "right" because there is no "right." The best creators understand that this is their world and welcome to it and I'm assuming that's what motivated writer/director Christopher Nolan in the latest film adaptation of The Odyssey.
Now, right up front, one has to acknowledge that even in a three hour film, which this almost is, there's almost no way to reasonably encapsulate all 24 books of the original poem, so things are going to be left out. Nolan does follow some of the same narrative pattern of the poem by first introducing Odysseus (Matt Damon) already living with the nymph, Calypso (Charlize Theron) and trying to remember everything he went through after he and his followers left Troy. To his extreme credit, he also weaves in a few more elements that would likely have been excluded, such as the eating of the lotus flower causing Odysseus' lack of memory (a different adventure in the poem) and the inclusion of the Laestrygonians destroying most of the expedition; a moment that most have likely never heard of if they hadn't read the original story. I also appreciate that he weaves in actual history to the proceedings, as one of the concerns of the time is the encroachment of the Sea Peoples, who are cited in the historical record as the most likely primary cause of the collapse of much of civilization after the Bronze Age (~12th century BCE.) So there's enough here to make an epic story. But I'm not sure there's enough to make an epic film. The main theme that Nolan operates from is the actual desire of Odysseus to forget what he has done and what kind of person it makes him. In doing so, it ascribes a very modern perspective to a very old story. I don't think there's anything wrong with that, intrinsically. Again, this is Nolan's interpretation and the theme that he assigns to the protagonist is a very understandable and, indeed, laudable one. It's not at all in tune with the poem, given that Odysseus and his crew raid the Cicones, allies of the Trojans, on the first step of their journey home and promptly sack their town, slaughter all of the men and sail off with the town's money and all of their women to be slaves of one kind or another. This is how it was done in 750 BCE.
Nolan also focused more on the case of the suitors than the poem does. That story is prominent in the poem, but not to the extent that it's the focus around which the story revolves. We spent almost as much time with Telemachus (Tom Holland) and Eumaeus (John Leguizamo) as we did with Odysseus. I realize that's an attempt to not only give an emotional attachment for a modern audience to revolve around but also to give some agency to Penelope (Anne Hathaway) who otherwise has comparatively little in the poem, in contrast to other women like Calypso and Circe (Samantha Morton.) If Odysseus is not only trying to get home for 20 years but is in conflict with himself over whether he even wants to make that attempt, it's nice to know something about the people he's going home to. But that focus on the suitors also meant that some of the other stories were kind of given short shrift. The most notable is the encounter with the cyclops, Polyphemus. In the poem, Polyphemus speaks normally as he's eating Odysseus' men and Odysseus eventually gets him drunk to get him to talk to them as humans, rather than dinner. That's the point where he falls asleep and they blind him in order to escape. But the whole point of that encounter is that Polyphemus, as a host, violates Zeus' law which is supposed to be emblematic of the collapse of proper society and was a main theme of the film. Instead, it's just a cyclops who looks more like a mutant derivation than an entire race of them (the island on which they land in the poem is inhabited by many of them) and the whole episode becomes just a run-in with a monster which, again, minimizes it and denies another opportunity to point out one of the central themes of the story.
Another of those themes was the rejection of divinity. Unlike in the poem, Odysseus frequently questions any kind of faith in the gods. That walks hand in hand with the perspective of a man who rejects the 10-year-war and wholesale slaughter that he's just been a part of, because why would the gods bless something like that? The fact that Agamemnon had sacrificed his daughter to make sure they had the favor of the winds is just reinforcement of that question. In that respect, I appreciate not only the central thrust of that idea but also that all of "the gods", with one exception, were left to appear as they were to the ancient Greeks: as forces of nature. "Zeus" was the crack of thunder. "Poseidon" was rough seas. Yes, "the gods" might have been there and Poseidon might have made it difficult for them to return because of what they'd done to Polyphemus (one of his many sons) but there was no way to verify that in the same way there's no way to verify the influence of any kind of divinity. That's what faith (or lack thereof) is and Odysseus was a man who had lost it, in more ways than one. The lone exception was Athena (Zendaya) who appears multiple times to simply ask the questions that bring the story along. I thought that was smart and it follows with Athena being one of the more human-approachable of the Olympians in many of the myths (the other one who has a significant role in the poem is Hermes, alas.) It's just too bad that it didn't transition from those elegant themes into the dialogue.
Straight up, the dialogue was weak. Most of it was boilerplate and overly obvious. If you had to fill the dialogue balloons of your average adventure story, these lines would've fit right in with little effort. I can't think of a single memorable line from the film, which is disappointing, especially considering the source material (i.e. epic poem.) Likewise, none of the performances really stood out to me except the two pig people: Leguizamo as the earnest pigherd and Morton as the witch who sees people for what they truly are. Given the opportunity to make Circe the villainess that many have presented her as over the centuries, Nolan stuck to the poem and made her a far more understandable and sympathetic character (She and Odysseus become lovers and live together for a year in the poem...) But, unfortunately, as with the rest, none of Morton's lines really stick out to deliver that. It was more about her ability to deliver through acting; again, to her credit. On a technical level, it's perhaps fortunate that none of the dialogue was that great, since a fair amount of it gets lost in the SFX noise. It might have been just a product of the sound system at the theater we were in, but I've heard other complaints about the sound mixing, as well. It's also notable that, despite the poem being replete with sex and sexual encounters, the film has none of that. That's not really surprising, as sex has never been a major driving force in Nolan's films and, again, this is his interpretation. It's just kind of funny to see such a major element of the poem become completely invisible.
In the end, it's a decent film that present an interesting moral quandary for its protagonist and one that I'd be willing to see again but one which I also think falls fairly short of most of Nolan's other achievements (Memento, The Dark Knight, Inception, even Oppenheimer.) I also appreciated some of the timing of it, not least the encounter with Scylla and Charybdis since we just finished our third chapter which revolves around namesakes of those legendary creatures. I wrote that story 15 years ago after first imagining my interpretations (ahem) of them 35 years ago because, of course, I'd read The Odyssey. I'd still recommend sitting down for three hours and watching the film, so that's my interpretation of it.