It's a very faithful adaptation of a seminal comic. The comic is pretty much the storyboard for the movie, as was the case with 300.
The superhero archetypes are deconstructed and put in a realistic setting. They have all the problems and foibles of real people, because that what they are under the masks. Only Dr Manhattan is what I'd call a true "superhero" (he changes the course of history as far as the Nixon-era setting goes), and his problem is the exact opposite. His power takes him emotionally further from humanity, to the point where he no longer sees himself as part of the human race. It's a great movie, and along with 300 shows what Snyder can do when given good source material. There's just so many good scenes, like Rorschach catching up with the child killer. What he does is horrible, but we tacitly approve and become complicit with Rorschach, because the system is broken and the crimes being punished are even worse. We understand Manhattan because he's fought back to his humanity, and then recedes away from us as he becomes ever more remote and superhuman. Laurie is caught between the ambitions of her mother, Jon becoming ever more remote as he becomes less human, and the new love who rescues her from that, not understanding that she's the last bridge between Manhatten and humanity. Ozymandius understanding and seeing all, working his plans within plans, finally revealing his ambitions like some mastermind, but twisting the trope at the last moment. What can you say about sociopathic, broken Rorsach, or the viscous psychopathic bully that is Comedian?
Snyder's later DC films have had moments of that brilliance, but studio interference and lack of good writing shows that you need more than visuals, you need to have some kind of connection or understanding of the characters. Watchmen is a brilliant, very underrated film, faithfully based on a brilliant comic.
