Spoilers:
If you had not read the book, this would be a fantastic movie, however, the film adaptation ruined Lucy Gray’s character. I’m the book, the whole point was that Coriolanus loves her but doesn’t know if he can trust her because of her past and her sneaky ways of surviving the games. Billy Taupe’s appearances back in 12 also serve to make her seem more sketchy. In the movie, she is made out to be a saint, never having to directly kill anyone and her past is completely breezed over. Several characters are completely removed which alters the storytelling. And rather than show Coriolanus’ distrust/hatred of Dr. Gail, they make it out to seem that he admires her throughout the film.
All in all, it’s a good movie on its own, as I understand that you can’t include ever detail, however if you wanted accuracy, this isn’t for you. The story is completely different and there are next to no dynamic characters other than Coriolanus.