After Earth movie explained
In the not too distant future, a climatic catastrophe compels humanity to leave Earth and travel outside the Solar System in search of a new home. The exodus comes to an end when humanity colonizes Nova Prime, a brand-new, uninhabited world. A thousand years later, the an alien race that sought to conquer Nova Prime, clash with The Ranger Corps, a group working to maintain peace under the command of General Cypher Raige (Will Smith). The Ursas are a race of enormous predators that hunt by "sensing" fear. Until Cypher masters the "ghosting" method of completely suppressing his fear, the Rangers battle the Ursas. He guides the Ranger Corps to victory after instructing the other Rangers in this strategy. In the meantime, Senshi, Cypher's sister, was killed by an Ursa, and Kitai Raige, Cypher's son (Jaden Smith), accuses himself of being responsible. Because of her passing, Kitai works hard to become a Ranger like Cypher because he doesn't want to let hi...