On Mars,The Guardians of the Universe created an interstellar police force called the Manhunters. The Manhunters served the Guardians until one of the Guardians,Oran Krona,reprogrammed them & have them evolved and rebelled. The Guardians destroys the Manhunters with the help of the Green Lantern Corps,who are given a Power Ring fueled by the strength of their willpower. After Krona was banished,One Manhunter escaped & swore revenge.
In the Presents,Test Pilot Hal Jordan is test a prototype aircraft. While flying back to Ferris Aircraft, a green light consumes the craft & flies Hal to the middle of the desert. The light brought Hal to a crashed starship with a dying alien named Abin Sur,who tells him that the ring chose him as his replacement as the Green Lantern. Hal is transported to the Planet Oa where he meets the Guardians & fellow Lanterns: Kilowog,Sinestro,Tomar Re,& Boodikka. As the first human Lantern,Hal begins training. Hal returns to earth where he learned that Carol Ferris is about to be promoted,which means he won't be in love with her. Suddenly,the Original Manhunter,Grandmaster attacked the city. Hal quickly saves Carol as the Green Lantern. Later,Carol learned of Hal's Identity,but despite that she gives him a kiss. At Oa,The Guardians explains to Hal about the Manhunters. Sinestro was outraged & betrayed by the Guardians secrets & leaves Oa.
Back on Earth,Grandmaster & the Manhunters attacked the Ferris Aircraft. Hal,Kilowog,Tomar Re,& Boodikka fought them as Carol fled in the Aircraft,but she gets blown into space. The Battery is ready & creates a destructive feedback loop,destroying all the Manhunters. Hal fights with Grandmaster,ripping out his core in the process. Hal feels depressed for the loss of Carol,but continues on being the Green Lantern.
Mid-Credits:
Sinestro discovers a new power in the light of Yellow.
Post-Credits:
The Surveillance is showing the Bank Robbers are outsmarted by a mysterious darting figure in the Red & Yellow Suit.