This is looking very bad.
I've been watching rottentomatoes ever since the film was released and the reviews aren't enthusiastic, to put it mildly. I'll watch it anyway, but I'm beginning to prepare for a disaster.
Right, some details may be better understandable if one has read the book (which shouldn't be a given in a film adaptation, but anyway). Some have complained, for example, that Marcus being called Aquila (which is Latin for Eagle) is childish, but then, it's a teen book, folks. Same goes for the rating not being higher than it is. I don't mind; I'm not attracted to blood and gore. It seems this is already far more violent than the book is.
But there are more serious issues. One is the political intent of the film. The opinions range from "non-existent, one-dimensional, unremarkable" to "loving ode to fascism", which I very much hope to be a misinterpretation, but it is worrying. The book is certainly nothing of the kind. Trouble is, the protagonist is a second century Roman soldier, and Rosemary Sutcliff made a valiant effort to describe what's going on in his head. He's an imperialist. Political correctness and humanitarian ideals are not part of his life and times. He never learned to question the ways and ideals of his own people - duty and honour above everything else. If that's coming through in the film, I see how it could be taken the wrong way.
But in the book Marcus is still a decent man, and he's honestly curious to learn why the British natives are so different, and why they oppose the Roman invaders so much for all the "good" they bring - law and order and civilization and whatnot. A central point of the novel is that he learns exactly why, and he learns to respect it. The natives Marcus and Esca encounter on their quest are not evil, and Marcus has no wish to harm them. He just wants to get the Eagle back (which, in the book, has also a pragmatic reason - the Romans fear it may give strength to those who carry it).
Oh yes, and all the while the book does not go Avatar on us and make Marcus change sides, to becomes the noblest and most savage among the noble savages. He remains a Roman, and he concedes that he will never fully understand the others. He doesn't have to. This is not about good or evil, right or wrong, but about tolerance, respect and friendship.
Oh, well. We'll have to see about that. Then there are those who found the movie dull and the script boring (I'm clinging to the hope that it's just the lack of romance and NC-17 action that bothers those), and a considerable fraction claims that the lead actor Channing Tatum has the expressive range of a sandwich and is not at all up to the role, which I fear may be true judging from the trailer. Maybe the German dubbing will help.
Anyway, there is talk of gay subtext, so there may be something to look forward to. *sigh*