There are good and bad things about this movie.
The fight scenes were nerve-wracking and they looked great. The use of propaganda and societal expectations in this film was okay too. Character motivations were fine, like David's motivation to go to war to be with Cassie.
The writing is not that great though. Not over the top amazing or horrible. I think the overall direction of the movie can do so much better without the love plot. While it does give the main character (Sergenat Dunne) a motivation to go back to war, I feel like it wasn't really necessary as it distracts us from more important events in WW1. They could've given him the motivation of avenging his comrades or something. The love story felt a little forced to me. They could've developed Sarah and Dunne's relationship more by having them bond more over their traumas.
This film is a bit historically inaccurate. Yes, the battle scenes were mostly fine but the scene where David is being rescued by Dunne with NO GUNFIRE???? HELLO???????? It doesn't make any sense. The Germans should've been shooting at them, especially since they had their backs turned. But they did get some things right, like the requirements to go to war.
Overall, it isn't the worst or best film.