An object is shot down over Seattle and the debris begins to affect the local weather, ultimately threatening the whole world.

A representative of an alien race that went through drastic evolution to survive its own climate change, Klaatu comes to Earth to assess whether humanity can prevent the environmental damage they have inflicted on their own planet. When barred from speaking to the United Nations, he decides humankind shall be exterminated so the planet can survive.

Sam Flynn, the tech-savvy and daring son of Kevin Flynn, investigates his father's disappearance and is pulled into The Grid. With the help of a mysterious program named Quorra, Sam quests to stop evil dictator Clu from crossing into the real world.