The movie, as best it can be summarized, is the origin story of how Hal Jordan became a Green Lantern -- which is a "corps" of heros defending the 3,600 sectors of the galaxy using the green energy of willpower. Hal, a cocky test pilot who followed in his father's footsteps despite witnessing the accident that killed him, is chosen by the ring of a dying Green Lantern, who just happened to be the most powerful of all of them. That Lantern -- Abin Sur -- once defeated Parallax, the greatest enemy of the Lantern, a creature powered by the yellow energy of fear, and it's up to Hal to stop it.
That is drastically oversimplifying the overall plot of the movie, which is a huge contributing factor to why it doesn't work. More often than not, plot developments seem to happen because they're supposed to in the Green Lantern universe, rather than as a natural consequence of characters' actions. On top of the Parallax story, or parallel to it as it were, there's a complicated mess of story with Hector Hammond, apparently taken from the pages of "Secret Origin", that just falls short of making sense, before coming to an utterly unsatisfying conclusion.
Part of the problem is Ryan Reynolds, who plays the confident side of Hal Jordan fine, but never quite seems to capture that bit of doubt they're going for with the character. The scenes in which he's expressing self doubt or coming close to succumbing to fear are supposed to humanize the character, but more often than not they drag the movie down. Not helping the situation is Blake Lively, who jumps wildly from self-confident empowered woman to wide-eyed damsel to wet blanket to supportive with really no explanation. The fault for that lies as much with the writing as it does with Lively, but its really on the latter to turn Carol Ferris into a living, breathing character, rather than a plot device to serve whatever role is needed at the time.
However, as I said earlier, the movie isn't a total loss. When focusing on the Green Lantern mythology itself -- particularly in the scenes on Oa -- it really shines. The scenes between Hal and Sinestro are probably the strongest in the movie, and I wish they'd spent more time on that, since the friendship and eventual conflict between the two characters is central to the comic.
Visually, "Green Lantern" is one of the more engaging comic book movies I've seen in awhile, though it doesn't really take off from that perspective until Hal visits Oa for the first time. I saw the movie in 2D, and given that it's just a 3D conversion, I'd recommend saving yourself the money, particularly because the darkening effect of 3D would really put a damper on some of the movie's brighter moments.
I'm sure there will be some people who will thoroughly enjoy this movie from start to finish, just as I'm sure there will be some who'll detest it. I think the majority of viewers will come to the conclusion that while it could have been much worse, it probably could have been much better too.
"Green Lantern" is rated PG-13 for intense sequences of sci-fi violence and action. Runs 105 minutes. Starring Ryan Reynolds, Blake Lively, Peter Sarsgaard and Mark Strong. "Green Lantern" opens nationwide on June 17.