(ALERT! Some people may think I give away too much in this review. I don't think so, but proceed at your own risk.)
This is not an easy film to evaluate. We saw it at an IMAX in 3D. That's a completely overpowering experience in itself, something qualitatively different, at least as I experienced it, than viewing a movie in a conventional theater setting.
The animation is astonishing. At first, one simply reacts in a sort of back-peddling way to the the 3D experience, which the film makers particularly exploit at the beginning with dramatic and explosive scenes. In addition, one is somewhat detached at first because the people in their animated forms seem less than real, but very interesting nonetheless. In other words, as you work yourself into the movie, you are a curious and fascinated and critical spectator. But after a while, your brain somehow settles down and gets involved. You start to live in the movie. That's a familiar place to be with a good movie, but this one somehow occupies you (or you it) more intensely simply on account of how the film makers put the thing together visually and aurally. Again, to an extraordinary extent it is the medium that takes you over.
The story is a different matter, and the characters, but I do not mean that the movie fails here. At first, the characters are interesting, as I already indicated, not as people as such but in their verisimilitude. But after awhile, you "forget" about that and actually accept them as "people". Although Beowulf, the hero, is a sort of screamer (at least at first) like the commander in 300, which I find annoying, he certainly becomes more of a human as the story develops than a lot of heros I've seen lately, including those in 300.
The story is about great temptation, great betrayal as one yields to it, and, finally, redemption, at least for the individual if not for the world. (What will happen to the world as it deals with evil is left hanging at the end.) I found that plot especially interesting because I have just finished reading The Kite Runner, another story of betrayal, an excruciatingly painful betrayal (I almost put the book down at that point), and redemption. Neither of these stories is written by Christians. (In Beowulf there is, in fact, gratuitous Christian bashing, which won't sell the producers any tickets to the evangelical community, and the author of The Kite Runner is of Muslim background.)
In both Beowulf and The Kite Runner, redemption is achieved by the works (and suffering) of the protagonist. But in The Kite Runner the opportunity for those redemptive works appears to be providential (or is it a plot-device, who knows). In Beowulf, the opportunity for redemption is provided by self-knowledge ("conviction"), guilt, and a second chance that the forces of evil themselves provide. In Beowulf's universe, as in ours, evil cannot keep a promise because that is the nature of evil, and that provides the redemptive opportunity.
The nature of the good is far less developed, even stunted in this movie. We see the unaccountable loyalty of Beowulf's wife and that of his friend, who engages in self-deception all the way to the end. The "gods" are remote and uninterested. There is only Beowulf and whatever he can muster. As I also indicated, we are not sure that this will be enough for anyone but Beowulf.
I have no idea of the extent to which the movie hews to the classic tale of Beowulf. I imagine it roams far afield. So it needs to be viewed on its own merits.
One other thing about the film I must mention is the beauty of Angelina Jolie. The animation moves her beauty to a place that no human can possibly occupy, something like, I suppose, what the Greeks did in idealizing beauty with their sculpture. That beauty dominates the last scene of the movie (this is not the scene from the trailers) and she is simply breathtaking. How could any man withstand her? In such a universe, where overhwelming beauty is the tool of hell, what hope is there?
The show has comic books aspects, of course, and sometimes it is simply crude, especially at the beginning. This is not Shakespeare or Homer or Tolkien. You have to allow for that. But as a total experience I would say that it is well worth seeing.
UPDATE: Good review in CT.