Poised to be one of the principle villains of the film, Nebula is a Marvel character who has been somewhat undervalued in the trailers for [Guardians of the Galaxy](movie:424073) thus far. We've only caught glimpses of the blue-skinned space pirate, though we're bound to see more of her rivalry against Gamora as the film approaches.
The most important thing you need to know about Nebula is that she is obsessed with Thanos the Mad Titan (the MCU's apparent big bad), claiming to be his granddaughter, which he later denies.
Though she doesn't really have any run-ins with the Guardians of the Galaxy in the comics (except for Drax and Gamora), Nebula is an essential character when it comes to Thanos and the Infinity Gauntlet.
Nebula made her comic debut in 1985, premiering in Issue #257 of [The Avengers](movie:9040). She was introduced as a dangerous space pirate working for Thanos' armada. She has massacred Xandar, antagonized the Skrull Empire and has even encountered the [Silver Surfer](movie:589196) on multiple occasions (she also appeared on the animated "Silver Surfer" TV show back in the 90s).
Of course, her most notable backstory for the MCU is that she eventually steals the Infinity Gauntlet from Thanos and acquires god-like power for a short time.
Interestingly, Nebula inevitably becomes an ally of Gamora by joining her team of female warriors known as the "Graces." In GotG, of course, we'll be seeing them face off, but the question of Nebula's true loyalty will definitely be up in the air.
Nebula has incredible strength and durability, along with a variety of weapons at her disposable. Her trademark wrist blasters can fire both concussive and heat blasts, and she has a device that can change her appearance and clothing. She is also a brilliant tactician thanks to her experience as a mercenary leader.
And that's about everything you need to know about Nebula. If I missed anything you think is important, use the comments to chime in!
Guardians of the Galaxy opens in theaters, August 1st.