As someone who read the Green Lantern comics growing up and into adulthood--I knew a lot of the characters' back story going into watch the the film...Given that, expectations were pretty high, and in the end the movie met most of those preconceived notions...
The film opens with a voice over that tells us millions of years before the Earth was formed, a group of beings called Guardians of the Universe, used the green essence of Willpower to create an intergalactic police force called the Green Lantern Corps They split the universe into 3,600 sectors, with one green lantern per sector. The strongest of all the Green Lanterns was Abin Sur (Temuera Morrison) of Sector 2814, who defeated the ultimate being of fear called Parallax (Voiced by Clancy Brown) and imprisoned him in the Lost Sector (Sector 666) on the desolate planet Ryut. However, as the story starts proper we see Parallax escape from his prison.
Six months later, he kills four Green Lanterns and decimates two planets, Parallax attacks Sector 2814 and mortally wounds Sur, who escapes and crash-lands on Earth. With his life ending he commands his ring to find a worthy successor on the planet.
Test pilot Hal Jordan is (Ryan Reynolds) whisked away to the crash site, where he is appointed Green Lantern. He travels to the Green Lantern Corps home base of Oa and meets Tomar-Re (Voiced by Geoffrey Rush) and Kilowog (Voiced by Michael Clarke Duncan) before encountering Sinestro (Mark Strong), who is not pleased that a human - which is primitive compared to other species - has become a Green Lantern.
On Earth, a secret government organization calls upon scientist Hector Hammond (Peter Sarsgaard) to perform an autopsy on Abin Sur's body In doing so a piece of Parallax's DNA inside the corpse injects itself inside him, mutating the scientist and giving him telepathy and telekinetic powers. When he realizes that his own father, U.S. Senator Robert Hammond (Tim Robbins), had manipulated him he attempts to kill him by telekinetic ally sabotaging his helicopter at a party. But Hal uses his Green Lantern powers to save the senator and all of the party guests - including his former girlfriend Carol Ferris (Blake Lively)
Hal eventually encounters the mutated Hector and through realizes that Parallax is on his way to destroy Earth....
Having a couple of Bond films on his filmography director Martin Campbell is used to handling a hero and bringing him to the big screen. Here he navigates the GG neccessities of the film quite well Oa for example--like Asgaurd in Thor--is perfectly realised without being overdone to take you out of those sequences--it pops just enough, I was also impressed at how much I didn't mind star Reynolds being in a CG created suit instead of "real" spandex pajamas.
The script from Greg Berlanti, Michael Green, Marc Guggenheim, and Michael Goldenberg stays true to the GL mythos but do think they gave Hal more one liners to suit Reynolds in the lead--than the he ever had in the comics No worries though--Ryan says the GL Oath with the weight that it needs at the right time. There's also a double father/son dynamic Hal & his father (Jon Tenney)~Hector and his dad Some of it works some of it does not.
Like a lot of these films in the genre there's a lot going on and certian elements of story feel squeezed Hector's arc is given a big build up and then goes woosh in the last act in order for our hero to be able to deal with the second threat of Parallax.
Blake Lively really sold me playing Carol--Never watched her TV gig Gossip Girl but she has gained a new fan as an actress. She and Ryan share that all important spark to make their relationship work...I also enjoyed Strong embody Sinestro with conviction and authority
GL sets itself up for a sequel...And forgiving a few miscues- I look forward to seeing what could be next...