The blue-skinned dwarfs known as The Guardians of the Universe are the founders of the Green Lantern Corps. Immortal; these aliens created the Corps to combat evil and to bring order to the universe. Strange as it may sound, these god-like beings have chosen to reject all emotion in order to be better in their self-appointed role as Guardians (boy, am I thankful that God isn’t like that).
Based on the Planet Oa, the Guardians guide the Corps through the writings of the Book of Oa which is sorta like a Bible or rulebook that they follow. Unfortunately, unlike the Bible, the Book of Oa is subject to change; as demonstrated by the Guardians rewriting or taking out bits that they disagree with at critical points. Heh… for immortals these guys are pretty fickle.
These guys have god-like powers to match but still they do have some weaknesses; one of them being the very rejection of emotions that causes them to make choices that even members of the Corps would disagree with. The Guardians can be very cold & calculating which is pretty much their biggest flaw as immortals. Anyways, I’m not gonna go into too much detail about the Guardians so for those of you who’d like to know more about them there’s a great Wikia entry here.
One of the more prominent members of The Guardians would be Ganthet (I don’t think I spotted him in the movie); so it’d be great to see something done with him in the sequel that’s sure to come.
I’m glad that they are taking things slow with the movie as there’s a lot of richness contained within the comic books. They’ve set enough up in the movie to allow for more exposition in a future film.
So there you go, the Guardians of the Universe; the founders and leaders of the Green Lantern Corps.