This film suffers from perhaps too much story, most of it not fully developed. In this respect it probably would have served the material better to have split it up into several different films as was done with The Lord of the Rings trilogy. To make a clear and convincing argument (in this case, that the human race is worth saving) it is important to develop not only the scope of the material, but also the depth. The relationships between characters only begin to skim the surface of what could have been a massive epic.