"The primary story of Oblivion takes place in Tamriel's capital province, Cyrodiil. There, the Emperor's throne is empty, and with its vacancy the gates to Oblivion (hell, essentially) are open. Demons are spilling through and attacking Cyrodiil's people and towns. You must find a proper heir to the throne in order to close Oblivion and restore order -- while also discovering what sinister plot triggered the chaos in the first place.

Oblivion will use a new AI system which Bethesda is calling Radiant AI. The developer explains that NPCs will now make their own choices based on the world around them. Each will go about its own activities, deciding when and where to eat, whom to talk to, whether to steal, go to church, etc. Bethesda is also adding full speech and facial animation for all NPC dialog."