The Comedian flying out the window. Jon Osterman getting zapped and later becoming Doctor Manhattan. The opening credit montage containing the Minutemen’s origin. Rorschach. There is so much Watchmen the movie gets right that it is sometimes hard to angry at what it gets wrong.
Watchmen is not perfect. It falls into a dangerous trap: For those familiar with the acclaimed graphic novel, you’ll either love it (look how awesome Rorschach’s prison escape looks!) or hate it (they changed the ending!). And even worse, those not familiar with the comic book will likely be easily confused.
For me, it was easy to ignore the missing stuff because I know what fills in the blanks. But for the viewer who has never stepped into the Watchmen world, much of the film will probably be confusing, or just seem dumb. Which is a shame considering how layered and perfect the novel is.
It was always said that Watchmen was unfilmable. The movie shows that the story is filmable, in a visual sense. Every major scene is beautifully captured on the big screen, and the film even comes up with its own gorgeous takes on the comic (Rorschach’s ending being an inkblot). What they didn’t realize was that Watchmenis unfilmable in the sense of character depth and theme.
The film never has any sense of urgency. While the comic constantly shows us the newspaper salesman discussing the imminence of nuclear war with Russia (every few pages for 400+ pages), the film eliminates this angle, and thus, removing much of the anxiety surrounding the pending holocaust.
Also missing is the pirate comic-within-a-comic story from the novel, which I think was the right choice.
My recommendation? Read the graphic novel first. The film was a sort of extra-visual companion peace to the comic, and in that sense, I was very pleased with it. But as a standalone product, the film lacks much of the depth, substance and complexity of the novel, which I feel is the best part of the Watchmen story.
Adrian Ruhi 
I agree with you — I’ve read the graphic novel and was able to fill in the missing holes. My problem with the movie, which I enjoyed, was the pacing. When you look back at the book after watching the movie, you realize that the story’s flow is actually slow. For every step it takes forward, it takes two back to tell a back story or to jump into the Black Freighter world. But when you translate that into film, it gets sluggish.
Also, and I’m hoping the Director’s cut will remedy this, certain events did not have the intended impact because of scenes presumably left on the cutting floor. (I’m thinking specifically of Laurie discovering who her father was, despite not showing the scene of her throwing the drink in his face.)
But overall, I agree it’s a great companion piece to the novel. And it was WAY more violent than I had expected.
The biggest flaw was not capturing Dr. Manhattan’s sense of time. In the comic you really get the sense of how alienated from humanity he’s become, no longer being bound by linear time. Always knowing the end before the beginning, normal humans were at best like children to him, and I don’t know that the film really brought that point home to watchers unfamiliar with the book. His performance was a little too Kevin Spacey for me.