(SPOILERS)
This movie had ALL the elements it needed to be one of the great movies of our time. It certainly had a great concept and a cast of superb actors (especially Millie Bobbi Brown). It could have easily been the "Aliens" of our time, and even could have resolved the one big narrative weakness of James Cameron's 1985 masterpiece.
Unfortunately the director must take the blame for turning what should have been a truly great movie into an average one.
Firstly, the script needed a LOT of tightening. This is primarily a movie about betrayal, and yet the actual villains of the movie are portrayed as paper thin caricatures. The scene where the ultimate victim (the dragon) learns the actual truth is handled SO clumsily I was shouting at there screen.
Secondly, there is too much attention to "action without purpose". Fights go on for FAR longer than necessary, (especially when both of the combatants are actually victims) and Elodie spends WAY too much time hiding behind rocks.
This is still very much a film worth watching. It just could have been SO much better.