I guess I am going to disagree both with the critics, wich of course is not at all unusual, as well as with a lot of the actual viewers of this movie by saying that I really liked this movie.
I guess that I can to some extent understand that some viewers are disappointed. That would be the viewers that have read the comics that the movie is based on. Unfortunately someone in the production team decided to take bits and pieces from several comic books and mash them together as well as change some key elements. It is really annoying when that is done. It is usually an indication that somewhere some dumbass who did not understand, and certainly did not respect, the source material had way too much influence on the production. It is really a shame since the comic book from wich the core of the of the story seems to be taken is certainly more than good enough to stand on its own.
Well luckily the mashup that they produced is actually bloody good. Something wich in my experience is quite rare. The Valerian comics lends themselves very well as a base for some spectacular sci-fi with plenty of weird creatures and spectacular scenery. Add Luc Besson to the mix and you have to spell spectacular in all caps.
This is definitely a Luc Besson movie. Plenty of action, spectacular (yes I repeat myself but this movie deserves it) scenery, a fair amount of weirdness. In short a lot of stuff this particular viewer likes.
The mashed up story is not too bad. It is predictable as hell of course, even though it is not following the comics, but it is making a decent job of tying together all the action and FX and the action and FX is really the main reason to watch this movie after all. I have to say that I think most of the characters were pretty okay. It seems that the performance of the two main characters where generally not so well received by a lot of people. I guess I can somewhat understand that but I still cannot refrain from saying: Read the fucking comics! Okay it is a French comic and there are probably few people outside of France (or at least outside of Europe) that have read them. Me being one of the few of course. Anyway, Valerian and Laureline are supposed to be somewhat weird, silly and a little bit childish. Personally I think they did a fair job of interpreting the comic book characters the way they should be. We probably have Luc Besson to thank for not getting a some Hollywood, thirteen on a dozen, characters.
I do miss some bits of the real comics though. The transmutation animal played a much more visible role in the comic and so did the three information peddlers wich gave a much more professional impression in the comic book by the way. I also think it was a shame that they changed the story of the Muh so much. Their role in the comic book was much more impressive to me.
Still, most of the bits and pieces that is taken from the different comic books and mashed together are quite faithfully reproduced, at least visually and the results turned out really really good as far as I am concerned.
To wrap it up, to me, this movie was a fun, spectacular, action filled sci-fi extravaganza. A typical Luc Besson movie and I mean that in a good way.